Computer Engineering Final Project

Facultat de Matemàtiques
Universitat de Barcelona

DESIGN AND IMPLEMENTATION OF AN

ACTION-RPG IN UNREAL ENGINE 4

ROGER RODRÍGUEZ CAMPRUBI

Tutor: Oriol Pujol
Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

Table of contents:
1. ABSTRACT
2. INTRODUCTION
a. Motivation
b. Objectives
c. Goals achieved
d. Memory structure
3. ANALYSIS
a. Game design
i. Concept Paper
ii. Game Design Document (GDD)
iii. Story Document
iv. Plot Document
v. Game Specifications
1. Weapons
2. Abilities
b. Technology
i. Unreal Engine and Epic Games
ii. Blueprint Technology
iii. File types
4. DESIGN
a. Project Structure
i. Classes structure
b. Level design

5. IMPLEMENTATION and TESTING

a. Wish I would have known
b. Task scheduling
c. Versions
d. Bugs
e. The BUG

6. CONCLUSIONS
a. What is
b. What should be and isn’t
c. What may be
d. What will become

7. BIBLIOGRAPHY

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

1 - ABSTRACT
This report you are about to read is a chronicle of how Iron and Time was developed.
Iron and Time is an Action-RPG videogame developed using Unreal Engine 4, a videogame engine
from Epic Games, and more precisely with its Blueprint Visual Scripting technology.
If you are unfamiliar with more than three words from the couple of sentences above this is a
great place to be! Through the report, we will take a deep look into Unreal Engine, we will learn
how to use it, what are blueprints, how do we script with them and why did we chose it to
develop this game. We will also take a look at the project structure to understand not only how
could it be made but also, and more important, how it is actually made. We will also explore
some difficulties we came across, including a very critical one (see THE BUG) to finally reach
some conclusions about the project itself and its future.

But I couldn’t start without giving my most sincere gratitude to several people whose help has
meant an invaluable asset.
I would first like to thank this project’s tutor, Dr. Oriol Pujol Vila, who has always trusted my
decisions and has offered his help in whatever I’ve needed.
To my girlfriend, who, despite disliking videogames, has listened thousands of times about the
game design, game story and game development, even contributing herself with her own ideas.
Finally to my parents, who one day thought it would be a good idea to give me a purple Gameboy
for Christmas.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

2 - INTRODUCTION

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

2.a – Motivations
To properly cover this point, let me first introduce myself briefly.
As everyone, there are lots of things I enjoy, from playing the guitar to travelling, all the way
through singing, songwriting, reading, programming, surfing the web, going out with friends…

All those things have made a spot into my hobbies/like-to-do-things through trial and error.
One day, after watching lots of guitar playing videos on Youtube I decided to try out how it was,
and did so with a classical one. While it was a good experience I wouldn’t define it as game-
changing. Things evolved and I got myself an electric guitar and started a band with some
friends. Some time passed and I also decided to start taking singing lessons. Today I still write,
play and sing songs for the same band of friends, and while we are not great at what we do,
that’s something I enjoy and is definitely an important part of my life.

“Hey man, what’s all this about, this a project memory! Go tell that to someone else and stay
focused here. What was all that speech about?”

Glad you ask! See, with the example above, I present an important part of my life that
successfully became what it is now, just as many others didn’t (I used to like swimming, for
example, but eventually left it aside).
Videogames were not like that, as soon as I was given my first gaming device (it was a purple
game boy color that was just released that year) that became instantly a core part of my life. I
could sink you in a boredom paradise explaining all the afternoons spent in front of my N64,
playing the games that would define what videogames are today.

My name is Roger Rodríguez Camprubi, that’s how most people call me, and the reason I skipped
starting with my name when I said I would introduce myself is because that hasn’t been my only
name for a long time now. I’m also known as Necrobooder or Booder by a lot of people who,
like I do, share videogames as a very important part in our lives.

I’m sure I don’t have to put effort in convincing you of my passion for games after what you’ve
just read, and it is that, my passion for games, where it lies the motivation for this project.

I enrolled Computer Engineering with a clear goal in my mind: becoming a game developer.
I was afraid initially, with the obvious common doubts: OK, love playing, what happens if by the
time you are able to program a game yourself you realize you don’t actually like it?
Fortunately, I didn’t have much time to think about it. Sooner than I thought, I was programming
my first Tower Defense game in my 2nd year of degree.

From then on, I have had a clear aim: I will become a great game designer, and this project is to
be my very first important step in the career of my dreams.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

2.b – Objectives
There are several goals intended in this projects and while each one leads to another one, it is
worth to mention them all instead of placing the final product as the one and only aim.

First of all, let me mention the initial goals I had with this subject, which are previous to the
election of the specific project:
 Get to know a professional game engine.
 Create a game that would serve as a presentation card for me, so I end the degree with
a solid portfolio to begin with.

After talking about this objectives with my tutor, we both decided that the best option was to
choose Unreal Engine, and agreed that the genre would be something in the lines of an RPG.

This decision came with a bunch of requisites that were converted also into objectives of game
design.
 The game must present an inventory, where the user can interact with objects picked
up in the in-game world.
 The game must provide some sort of progression for the character.

And with global and specific objectives written we have only the micro-objectives to be
considered. These are the ones which are assumed by the others but are used as an immediate
goal in development to have something more specific to work towards.

Learning objectives
This are the pre-requisites to start developing.
 Learn the very first basis of game design, so the project does not start with a mess of
crazy ideas but a well-organized documentation about crazy ideas.
 Learn about Unreal Engine 4, what is it used for and how does it work in general terms.
 Learn about the blueprint technology and master it enough to build a game with it.
 Learn about animation management (not creating animations) in UE4.
 Learn about level management and level creation in UE4.
 Learn about cinematics and audio treatment in UE4.

Design objectives
While we could put all game design here and set it as an objective, there are some main features
that represent the whole of it.
 The progression system will be based on weapons, and there will be 5 ranks of them.
 The game will provide a weapon-combination system
 The character will have different abilities depending on the weapon wielded.
 There will be an engaging plot, with its basis in a solid fantasy world that drives the
player from the beginning till the very end.

Technical objectives
This are the ones everybody would expect from a game like this, but it’s important to
acknowledge them, for they are key to the implementation process.
 The game platform will be the computer.
 The player will be able to fully control the character.
 The camera will be set above and behind the character, pointing its back from what
would be ~10m in real life and will NOT rotate with the character.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

 There will be enemies controlled by a simple artificial intelligence.

 There will be an inventory to store picked up or looted items.
 The player will be granted a GUI to interact with the inventory.
 The player will be granted a GUI to combine weapons.
 There will be illuminations, animations, particle effects and sound effects to grant a
proper immersion level to the game.

There are parts of game developing which I will not cover which are mostly the artistic sections
(such as modeling and animation). I will get the models, animations, and textures (including raw
images) from the Epic Games marketplace.

2.c – Goals achieved

If there’s something we can tell about the previous section is that the project itself is ambitious
for someone who know nothing about the tools he is going to work with. So, before beginning
to explain about the process, it is important to know where we arrived:

Did I achieve all the goals? Simple answer, no I did not. Explanation below.

It will be covered in its own section in this paper, but I had to stop working on the project on
December 11th due to what seems to be a bug in UE4 editor. This means I lost way more than a
month, which would have been enough to get the project perfect (objective-wise).

Reasons apart, where did we arrive? We get to a point where the core part of the game is
working. We have:
 A basic but still complete scenario.
 Final models for both the main character and the friendly and enemy NPC’s
 All interfaces working, including
o Description panel (when you mouse-over a character, item or ability)
o Inventory UI
o Forge UI (weapon combination system)
o Resources managing UI (health and resource bars, abilities bar)
o Pause menu
 Fully functional IA, both for enemy and friendly NPC’s
 All items and weapons in the database, with its thumbnail, model and features
 All level 1 and level 2 abilities implemented (12)(remember, there were 5 levels with a
total of 52 abilities)
 Fully working level, with triggered events.

The best way to keep a track of how the project was going with my tutor was via videos, which
I recorded and uploaded to Youtube. This is the latest one, which corresponds to a version of
few days before the project collapsed.
https://www.youtube.com/watch?v=9pA-7spR_M0

So, that’s what we have. What I’d like to do now is to make a difference between a finished
product and the desired final product, for they are different things in this case.
Although I will expand on this in its own section, I’d like to state a few things before we continue.
A finished product is something that has a meaning on its own. It may not be the initially thought
product, but it will be unnoticeable to anyone who does not know what the initial idea was. Our
desired final product is summarized by the objectives in the previous section and would need
to accomplish all of them.
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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

What would make the current version a finished product?

Actually, the things that would achieve this are the ones I was working on. The current version
would need this to be considered a final product:
 Dialog system, so the friendly NPC can provide the player instructions in what to do
 Audio, both ambient music and sound effects.
 Possibility to save and load the game.

What would make the current version a final product?

As I said, I will expand on this later, but to be quick, it lacks the following, aside from the 3 points
stated above:
 Plot integration, and this would come with more levels and storytelling (and probably
cinematics too).
 Implementation of the rest of the abilities (I only implemented the ones that were
obtainable in the tutorial level, so because there is no way to obtain more advanced
weapons (more levels would be needed for that) there was no need to implement yet
their abilities)

What I was trying to say with all this, is that the game is missing the game itself. It has the
mechanics scripted, the GUIs working and all the core functionalities in good shape, but it just
has a tutorial level to test a very little part of them.

To close the section: This was not the state the project was intended to end and nevertheless, it
still is a good piece of software to show what I’ve learnt and how far I could have arrived with
6+ more weeks of effective time.

2.d – Memory Structure

As it is stated in the table of contents, this memory consists of 7 parts. Aside from the abstract
and the introductions, which we have already covered, it has:

 ANALYSIS: Everything about game design is covered here, also, all the technical
knowledge about UE4 and its features is also explained in this section. When we end the
analysis we should know everything needed (both design-wise and tech-wise) to start.
 DESIGN: This section covers the architecture of the project, what classes do what, and
generally how all the previously learnt knowledge is structured to become a game.
 IMPLEMENTATION and TESTING: This part covers the development process, the order
in which things were implemented, what versions were generated, technical concepts I
learnt during development phase and the troubles and bugs encountered.
 CONCLUSIONS: This last section deeply explains, what was achieved, what should have
been done to be a better project, what ways could we expand this game and how the
game is intended to evolve after it is delivered.
 BIBLIOGRAPHY: Although there were not a lot, this final part states all the information
sources used and tires to state every single asset source to give them credit for their
work. Finally it includes a “Thanks to:” section.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

3 – ANALYSIS

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

3.a – Game design

The first stage of the game (even previous to the technical learning process) was to design the
game. We had two choices here:
 Develop an idea briefly, to have something to work on (designing the camera, the
control and a few key features as the inventory), start implementing and, once the core
is done, start designing additions like the progress system, enemy differentiation,
friendly NPC’s etc.
 Fully design and document a game without opening the editor and start working only
when about an 80+% of the design is done.

Both of them have their pros and cons but since I wanted to put a lot of importance in game
design instead of focusing purely in game programming (remember I have said earlier that my
final goal is to become a game designer, not a game programmer) I chose the second choice.

The very first thing I did when designing the game was finding the key game mechanic. I already
had a few ideas written down (as I normally write my ideas so I don’t forget), but none of them
was the proper one. I came across weapon combination; it was something I’ve enjoyed a lot in
the games I’ve played that implement some kind of it, and I decided to do it the main progression
system. Then I started brainstorming to see some different ways it could be implemented and I
actually write down the first concept of what later would become this game’s GDD (Game Design
Document).

After that, I tried to learn a little about game design process and early documentation, and I
came with lots of theories, most of which had some common points. Using this knowledge and
taking into account that I was not working in a team where every single detail must be written
down to ensure ambiguous meanings don’t lead to a fail, I decided to structure my design
documentation in the following way:

1. Concept paper: Game design is all about the experience. How the game will provide the
player the intended experience is the game designer’s main job, and a concept paper
consists of the key features the game will have to achieve that. It does not cover in-game
mechanics, lore or level-design. It is the first document to be done and it contains the
basis all the other game design will use.
2. Game Design Document: This document is the bible of the game. In a professional level
EVERYTHING must be written here, from the character gender to the position of the
“resume” option in the pause menu. Since most of the sources agreed that the most
valuable game design document is the one that is actually useful, I decided to limit a lot
what would be in it. In my case it contains all game features, not the way they will exactly
be placed in the game, but the logic behind them.
3. Story document (Lore): It was important for me to set the plot in a contextualized
fantasy world. If I was to create and engaging story it couldn’t come from nothing. In
this document I tell the story of the world in which the game takes place. Lots of stories
could have its place here, and this game’s plot is only one of them.
4. Plot document: This document contains the plot of the story, everything in here is what
the player will be doing while playing the game.
5. Game specifications: Normally these would be part (or could be part) of the GDD, but
since they are closed concepts they are more useful in their own documents, it covers
the abilities, the weapons and few other in-game concepts.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

It was not until I almost finished the game-mechanics design that I start thinking about the story
and the name of the game.

Believe it or not, the way I came up with the name is pretty unorthodox. I am very bad at both
2D and 3D art but still needed a good game logo, so I wrote down some names that could fit
well in a fantasy title, things like fire, nether, soul etc. Then I googled for copy-right free images
of that name and the word “Iron” just happened to have a cool typo in a flat image. I started
from there and thought about the big picture of the lore. After that, I came with the final title
for the game: Iron and Time.

Lastly, I finished the lore document and thought about the story of the game itself, but I wouldn’t
write it down until I had enough experience with the editor and the language to know how far I
could reach.

The following sections are the documents mentioned previously as they were written mid-
September, there are things that can’t be seen at the game, but if they’ll most likely be once I
can finish the game. They do not have title names for each section, instead the documents’ name
is written in the header of each page.

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 Iron and Time – Concept paper Roger Rodríguez Camprubi

IRON AND TIME – CONCEPT PAPER

Iron ant Time is a 3D action RPG, with a 3th person camera that looks similar to games like
diablo.

As an RPG it has a progression system which is based in weapon upgrading instead of character
level progression.

It has a strong, deep storytelling that reinforces the gameplay and gives it coherence.

The game has a big map, with 3 environments which offer interaction between the world and
the player.

The combat system is the classic Arpg horde-style. Lots of ‘weak’ enemies attacking at once or
few stronger ones. It includes 4 epic boss battles.

The main feature of the game is the ability system which relies entirely on the weapon
wielded.

A player can gain expertise with different weapons (and will need to) in order to customize
their abilities and progress his/her way to the end boss.

Weapons can be combined with other weapons to enhance their skills or upgraded via
amplifications.

All the art is medieval-like, except some enemies.

The combat system is engaging, fun and fully customizable.

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 Iron and Time – Game Design Roger Rodríguez Camprubi

QUICK INTRODUCTION:

 Character is able to wield various types of weapons, and they (the weapons) will be the
main progress system and the main feature of the game.

 Weapons split in Types and families. There are 3 types with 3 families in each one.
- Melee
 Axes
 Knives
 Swords
- Distance
 Bows
 Crossbows
 Lances
- Magic
 Staffs
 Wands
 Tomes

 Character progression is based in his expertise with each weapon family, NOT in the
character itself.

PROGRESSION SYSTEM

 Weapons are classified in 5 ranks, being 'ordinary' or 'Rank 1' the lowest and
'worldbuilder' or 'Rank 5' the highest.

 Each rank will increase all the stats the weapon grants to the player (such as defense,
attack power, health points etc.)

 Evolving a weapon's rank can be done by the following methods:

- Combining weapons: 2 to 3 weapons will be fused. The weapon placed at the first
spot (in the fusing GUI) will act as 'host' and preserve its ability.
- Embedding an amplifier to a weapon: An amplifier will be embedded to the
weapon giving it new powers.

 Each rank upgrade has a system to follow which is:

- 1-2: Combine two copies of the same weapon to upgrade it from 'ordinary'(rank 1)
to 'master'(rank 2)
- 2-3: There are 2 options to upgrade a weapon from rank 2 to rank 3:
 Embed an amplifier to a 'master'(rank 2) weapon to create a 'heroic'(rank
3) weapon
 Combine 2 'master'(rank 2) weapons from different TYPES to forge an
'hybrid'(rank 3) weapon(i.e. a bow with an axe or a knife with a staff)
- 3-4: There are 2 options to upgrade a weapon from rank 3 to rank 4:
 Combine all 3 'heroic'(rank 3) weapons from the same family to forge a
'legendary'(rank 4) weapon
 Combine all 3 'hybrid'(rank 4) weapons to forge a 'chimera'(rank 4)
weapon
- 4-5: Embed a primal fragment to a 'legendary' or 'chimera' (rank 4) weapon to
upgrade it to a 'worldbuilder' (rank 5) weapon.

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 Iron and Time – Game Design Roger Rodríguez Camprubi

 Additionally each upgrade requires the character a certain amount of expertise with the
'host' weapon.

Example of a 'worldbuilder' weapon crafting path

 Crafting materials:
- 'ordinary' weapons will be obtainable from all kind of sources (mobs, treasures,
vendor)
- Amplifiers will require to be crafted, as explained in the following section.

 Amplifiers:
- All of them need to be crafted from:
 farmed materials (like copper ore or dry wood, obtainable from world
sources)
 mob resources (like skeleton bones' dust, obtainable from killing mobs)
 purchasable items (like soft rosin)
- There are 2 kinds of them:
 Artifacts of power (AoP): are used to upgrade a 'master' weapon to a
'heroic' weapon. Consist of 3 parts:
 Essence: the essence contained within the artifact. There are 9
essences obtainable by killing enemies:
o Essence of Momentum
o Essence of Justice
o Essence of Greed
o Essence of Insanity
o Essence of Focus
o Essence of Lethality
o Essence of Purity
o Essence of Darkness
o Essence of Might
 Retainer: Acts as an essence recipient and transfers its powers to a
weapon. There are 3 types which can be crafted from farmed
materials:
o Relics - used to capture essences into Melee weapons
o Runes - used to capture essences into Ranged weapons
o Blessings - used to capture essences into Magic weapons

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 Iron and Time – Game Design Roger Rodríguez Camprubi

 Catalyst: Captures an essence in a retainer. Can be bought from

NPC’s.
Each retainer type can capture any type of essence, giving 27 total possibilities.
 Primal fragments: are used to upgrade 'legendary' or 'chimera' weapons to
'worldbuilder' weapons. As Artifacts of power, they need a specific
retainer (which will use all types of materials in the game to be built),
Primal Essences, which can only be obtained from higher level mobs, and a
Catalyst that can be obtained by certain NPC’s.

ABILITIES SYSTEM

 Each weapon type will hold its own combat resource system:
- Melee: While in combat, a melee weapon wielder will generate fury over time
during combat, when using autoattacks and when receiving damage. This fury shall
be spent in abilities. In a normal off-combat situation player has no fury.
- Distance: Distance weapon wielders will gain clarity whenever they move, which
they will use to cast their shots. In a normal off-combat situation player has full
clarity.
- Magic: Magic weapon wielders will use mana as they resource to cast magic spells.
Mana will slowly regenerate over time and will recover a lot faster after 3 seconds
of dealing no spell damage. In a normal off-combat situation player has full mana.

 Character has 2 to 4 abilities which rely on which weapon is he wielding and follows this
structure:
- '1' ability is specific to the weapon type.
- '2' ability is specific to EACH rank 2 weapon.
- '3' ability is specific to EACH rank 3 weapon.
- '4' ability is specific to EACH rank 5 weapon.

 Additionally, the character will continuously auto-attack (assuming it is in range) the

targeted enemy.

 All the ability configurations will manage to work out in a way that abilities interact with
each other.
This example shows abilities that ARE NOT related and don’t create synchrony.
1. ranged skillshot
2. surround-aoe
3. mobility
This example shows abilities that ARE related and create synchrony.
1. Charges a big fire ball on the player.
2. Sends the fireball in a straight line
3. Explode the fireball around its current position.
This way you can use '1+3' to cause a great explosion around you or '1+2' to shoot a
charged ball to a distance, '2' to shoot a tiny ball or even '1+2+3' to cause a great explosion
at a distance.

 Using this system you get Rank 1 and 2 abilities early in the game, so you have a non-
boring gameplay experience while you get familiar with the weapon system and the
weapon type specific resource. Once we know a little bit of everything and can choose
with a fair knowledge about choices, we get our 'heroic' weapon and get a full-operative

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 Iron and Time – Game Design Roger Rodríguez Camprubi

 Set of abilities that combine with each other in a different way than another 'heroic'
weapon of the same family would have.
At the end we get our 'worldbuilder' weapon and our 4th ability which is like an ultimate
spell that identifies the weapon family (The BEST sword technique ever or the most
destructive spell ever casted from a tome) and fulfill the need to feel powerful.

 This system lets the player feel different when wielding a 'darkness sword' from when
wielding a ‘lethality knife’, although they are both melee weapons which use the same
resource.

BIG PICTURE

 This way we will have the following set of choices:

- RANK 1: 9 'ordinary' weapons with 3 rank 1 abilities
- RANK 2: 9 'master' weapons with 9 rank 2 abilities
- RANK 3: 27 'heroic' weapons and 3 'hybrid' weapons with 30 rank 3 abilities
- RANK 4: 9 'legendary' weapons and 1 'chimera' weapon and NO rank 4 abilities
- RANK 5: 10 'worldbuilder' weapons and 10 rank 5 abilities

This leaves us with a total of 68 weapons and 52 abilities BUT it opens us an incredible level of
customization. IE:
"One player can have 2 'identical' weapons that only share 1 ability. It would be the case of the
hybrid 'worldbuilder weapon'. We can get there starting from a knife and getting: Melee rank 1
ability, Knife rank 2 ability, weapon-specific 'Heroic' rank 3 ability and 'Chimera worldbuilder'
ability. OR we could go wand and getting: Magic rank 1 ability, Wand rank 2 ability, weapon-
specific 'Heroic' rank 3 ability and 'Chimera worldbuilder' ability.
This way we would end up with 2 copies of the same weapon with two completely different
sets of abilities.

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 Iron and Time – Lore Roger Rodríguez Camprubi

THE LEGEND OF IRON AND TIME

Ages ago, much before life was created, the so called “worldbuilders” were a group of beings
whose origin was unclear even to themselves. They were blessed with the gift of creation, and
they were able to materialize their minds. Therefore, it must be said they were very primitive
creatures and although their powers are beyond the imaginable, their thoughts were small and
their methods loose.

With time they learned to improve their skills but they also acknowledged their limits. They
learned that only truly comprehended things can be created, and not everything was
comprehensible; at least, not for everyone.

They did not have such thing as a name, but for the sake of coherence, we, mortals, have given
them many names through the years.
There was Gyvenimas, who brought life to things. Organas, who was capable of shaping its
mind and give it a body. Zinios, who gifts with knowledge and self-conscience and Galia, who
infuses power on creations.

Centuries went through and they realized nothing would come from working alone and started
collaborating together to create what would be called “worlds”. Each world was better than
the previous, but still they knew, even at the beginning, that no perfect world would ever be
created. Their perceived perfection as the greatest thing they could imagine: themselves.

Creating a life-being that could inherit the gift of creation and break the limits each one of
them had become their greatest goal, and as their progressed in building worlds they also
started to develop a plan to achieve their milestone.

They would create an iron orb and set it at the very center of a planet, then they would merge
themselves with the orb, creating what we know as ‘the orb of creation’.
With time, harmonic energy would emanate from the orb cleansing the planet of any
imperfection, and, once it reached the surface, it would start creating the first beings of a new
race. The one which should be the definitive.

They were convinced on the plan despite it would mean their end, but a better generation of
worldbuilders was to born and the price seemed insignificant for the gain.

The project worked really well, but Gyvenimas, who valued its ‘life’ more than it had suspected
until the time, could not control the impulse of breaking out of the orb moments before it was
sealed. That move would not only sentence their relatives but it would also prevent the new
race from receiving the gift of creation, as it could not be inherited without the gift of every
single one the worldbuilders. Without Gyvenimas essence the races on that planet would born
as mortals, with a time set for their deaths.

And here we are, the imperfect sons of greatness. Condemned to an unplanned fate that will
forever doom our race.

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 Iron and Time – Lore Roger Rodríguez Camprubi

ESSENCES
The gift of creation was not transmitted to mortals, but that does not mean it disappeared.
Each and every race that existed in the planet before the creation of the orb has been altered
by the emanating forces of the iron of creation, imbuing themselves with one of the essence of
creation.

This essences are:

 Essence of Momentum: Contains unlimited rage in a controlled attack. Unstoppable,
unceasing but still, clever.
 Essence of Justice: Contains the essence of the Executioner, the right choice can be a
hard one, but it must be done with honor.
 Essence of Greed: Contains an unlimited hunger for power. The bigger the better, the
deadliest the best.
 Essence of Insanity: Contains death without control, without limits, unconscious.
 Essence of Focus: Contains precision an agility. It may take 5 stabs to take it down, but
if no more are needed no more will be served.
 Essence of Lethality: Merciless, it can take time, and pain, and suffering, and agony.
They'll witness their own decay.
 Essence of Purity: Contains de will to protect, patient but unbreakable.
 Essence of Darkness: Contains pure evilness, it's corrupted and it will corrupt.
 Essence of Might: Contains the soul of those privileged, proud and confident, almost
arrogant.

THE BIG BAD GUY

The role of the villain is obviously reserved for Gyvenimas who, after quitting the orb was not
able to escape the world and hides from creation at Eldora cavern. It has secretly been
extracting the essence of Organas, Zinios and Galia from the orb and capturing them into
mortal bodies.

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 Iron and Time – Plot Roger Rodríguez Camprubi

PLOT

PROLOGUE

A young man wakes up. It’s midnight and he’s swearing. Again. Over time, he has faced his fears
alone, for he had no one else. But this feeling in the air has been around for weeks now… what
is it? Too vague to be real, yet too real to be a mind trick. There’s something there, and he knows
he’s not in the position to do anything. He grabs the old wood piece he found years ago, in the
place of the forest his house used to be, he stares at it and reads the two only words written on
it: “you are”. He knows anxiety will not disappear and tries to calm down. He turns around and
lies down again, and just before closing his eyes, a voice from the dark side of the room whispers:
- Good night – the voice doesn’t convey fear, and it happens to be relaxing somehow –
it’s the time you come with me.
- What do you want from me?
- I want nothing, I’m just a messenger.
- Then who is behind this?
- This is not the right question. Perhaps “what” would have fitted better. Destiny is calling
you and it’s not known for its patience. The Iron Council awaits you.
- I have no interest in it.
- And this isn’t the right answer.
A light turns on and he realizes what’s happening before falling to the ground. The whole room
is full of poisonous gas. It barely smells, but once it reacts to fire, it quickly knocks him off.
He is undamaged, but he’s also unconscious.

He wakes up again, no swear this time, no darkness and no fear. He unexpectedly stands in the
middle of a room. It’s not a huge room but ceiling is way too high to be seen properly. One man
speaks:
- Are you in disposition to listen?
- I guess so – he answers.
- What do you know about the gift of creation?
- I’ve never believed in those who think we were supposed to be gifted, but accidentally
aren’t.
- Have you heard about the Legend of Iron and Time?
- Have you heard about the monkey merchant fable?
- Have you heard about what “disposition to listen” means?
- … - That was a good one – Hell… I don’t get to choose right? Go on old man.
The man nods
<- The Legend of Iron and Time->
- What’s the point of this? – The man asks – was I brought here to listen stories?
- Gyvenimas is alive and in this world.
- Oh man, things start to get better – joked the man
- And we suspect you might be the last man alive with reminiscences of the gift.
- What? You just can’t believe what you’re saying.
- I don’t expect you to understand…
- How would you? I thought loneliness made me crazy, but it’s a relief to see it didn’t.
- You don’t understand.
- What should I understand? This is not an epic, where you send your minion hero to a
long journey with an “It’s dangerous to go alone, take this…”
- YOU DON’T UNDERSTAND.
- And I’m not even willing to! Look, I’m no hero, and even if I was I’m not interested in
your tales at all.

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 Iron and Time – Plot Roger Rodríguez Camprubi

- You. Don’t. Understand.

- What’s this?! I never asked for it! Nobody needed me till they did. And what am I
expected to do? The world has given nothing to me, and that what he’ll get back. I’m
not playing hero.
- You are not the hero, you are just the catalyst.
It was not mystical at all, there was no burning fire, no flashy magic. A knife cut his throat before
he could even notice.

This part of story serves as a prologue, lore introduction and controls tutorial to the game.
During the very first part of it (the part when the man wakes up) the story is told in a frame in
the screen and possibly voice-acted. When the story reaches the point where the man grabs the
wood piece, the player must move the character from the bed to wherever the wood piece it is,
pick it up, and return to the bed. After that, the player gets to talk with the messenger and then
the scene fades. All the second part should be a cinematic. And at the end of it, the game title
“Iron and Time” is presented.

The story resumes with a man talking to the Iron Council man.
- Have you understand? – asks the old man.
- I do, I guess everyone relies on me now.
- Not just everyone, everything, the entire fate of our kind depends on you. The whole
universe awaits your success.
- Ok old man, count on me. Gotta prepare if I want to make it out of the forest alive, and
there are a couple of things I will need to know if I intend to take this challenge.
- You don’t need to hurry, a solid step is more valuable than a fragile sprint.
- Yeah, whatever… See you again then!

The player enters a portal and it teleports him to the tutorial level.

The tutorial teaches the player the basics about using abilities, equipping weapons and
combining them to get more powerful ones. At the end of it, the player is given a note which
specifies its concrete objective:
The Iron Council needs a rare item which they call a “primal fragment”. It is supposed to contain
the purest source of the gift of creation available, but it is uncertain where it lies.

Eventually the character will find out that Organas, Galia and Zinios have been revived into
mortal bodies under the command of Gyvenimas, and that it is by defeating them how he’ll be
able to obtain the primal fragment.

The whole map will be based in 3 different environments (magma, forest and glacier) and each
one will be the room of one of the Worldbuilders.

The player will only be able to access to Organas area in the magma zone if he’s wielding a
worldbuilder (rank5) melee weapon, Galia in the forest zone if he has a worldbuilder ranged
weapon equipped and Zinios in the frozen zone if it has a worldbuilder Magic weapon equipped.
If he has equipped a chimera worldbuilder weapon he will have to fight a combination of all in a
special zone he will enter from any of the other zones.

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 Iron and Time – Plot Roger Rodríguez Camprubi

Just to clarify, the player will be able and will have to go to all 3 zones in order to evolve its
weapon, just that the part where the boss is will be blocked until a weapon of the specified
characteristics is equipped.

After defeating the mortal body of any of them, the real worldbuilder within will make his way
out and reveal the prologue story to the character, stating that the Catalyst he has is in fact the
result of subjugating the last gifted man’s soul, and it will also tell him about their initial intention
and how they failed to believe they could create a specie capable of controlling the entire power
of the gift of creation and apologizes for how naïve they were. Finally it states:
- You are certainly chosen, everybody is. But not by the Iron Council, neither by me, or
any of the other Worldbuilders… Sukürimas is how we call the force that rules the
universe, it created us to create your people, and it wanted your people to create you.
You are the one who decides. Once you strike Gyvenimas you will be chosen one to take
the ultimate choice. The Iron orb will finally be completed and it is in your hands to
decide whether creation should rely on Entropy, by destroying the orb, or in what you
humans call “God”, by claiming its power. Arrived the moment you will have no time to
think, so I suggest you think about it.
Then the worldbuilder will fade and so will do the scene.

The player will appear at the Iron Council catacombs with the Primal fragment. After
conveniently explaining the story to the old man he will tell that the Iron Council has located
where Gyvenimas could be and explain that an unstable vortex originated at a forest. Once the
player gets to that place he will find a wood piece with an inscription on it “You are”. It means
that place is where the parents of the “catalyst” man and he himself lived years ago. Gyvenimas
was there to erase the last bit of gifted people in the earth but did not know the couple had a
son that was not in the house at that time. All this is by the player to figure out.

After entering the portal, the player will face some of the most powerful enemies in the game,
and finally Gyvenimas. After defeating him he will say the following:
- How could I ever agree to destroy myself, I am Gyvenimas, I am life! I was created to
live, not to sacrifice!
…
Is it all written? Was I expected to flip the coin, to become death?
Do our choices matter?
I regret nothing, this is what I am, and if you take the orb, you take its meanings.
I will not attempt a change myself again, this time Sukürimas will be the one deciding…
At the end of the day, it has always been this way. Are we really responsible of who we
become?
…
Huge responsibility in your hands kid. Don’t waste the time, and ensure you are the one
who makes the decision.
Do not hesitate… not this time.

And the game ends.

20
Iron and Time – Weapons Roger Rodríguez Camprubi

ordinary axe
master axe Big but light, perfect to slice Meteoric jump
ordinary axe
ordinary knife Equally sharpened, but much more
master knife versatile. Shadow step
ordinary knife
ordinary sword master Weapons are like friends, the more loyal,
the more you can abuse them. Quick dash
ordinary sword sword
ordinary bow A better grip allows you a much higher rate
master bow of fire. Rapid fire
ordinary bow
ordinary crossbow master
More resistance also means more power. Landmark
ordinary crossbow crossbow
ordinary lance
master lance If I can’t break it, it must be good Shove
ordinary lance
ordinary staff This staff twists time as it twists its owner’s
master staff mind Timestamp
ordinary staff
ordinary wand
master wand This wand expands the limits of the space. Teleport
ordinary wand
ordinary tome Now you don’t feel the magic, you ARE the
master tome magic. Combustion
ordinary tome

master axe When there’s no other goal than victory

Harvester each hit you strike can mean a victory Charge
relic of momentum tomorrow.
master axe You will never break the wall, for you
Judicator have no rights. I do, and it is my duty to Wallbreaker
relic of justice break it for you.
master axe You wouldn’t be able to wield it without
Axecallibur breaking your arms. I, on the other side, Heavy metal
relic of greed make it dance with a finger.
master knife One after another, like a lighting storm.
Razor whip It hasn’t got a purpose, but death does Blade storm
relic of insanity not require one.
master knife First gash will barely be noticed, second
Scalpel will hurt, third will make you agonize, Surgery
relic of focus there will be no fourth.
master knife The blade is so hot you don’t even feel
Melter the penetration. Death was inside, but Blood boiler
relic of lethality nobody had knocked the door.
master sword Purity was the essence archangels made
Oratie their swords of. This sword carries a part Counterattack
relic of purity of heaven within.
master sword Everyone has power inside, let me grab
Blackhowl some of yours. Dark pact
relic of darkness
master sword Those of you who are willing to follow
Emperor
are expected to wait, are expected to Nomination
relic of might sword earn your title. Rush and it will be over.

master bow The bigger may not always be the Overly sized
Driller better, but it’s for sure the
rune of greed most painful projectile
master bow If the stars align, you will receive no
Mistwhisper mercy. Execution post
rune of lethality

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Iron and Time – Weapons Roger Rodríguez Camprubi

master bow Let it in, let it flow, let it work. And

Shadowspark finally, let it spread. Infection
rune of darkness
master crossbow You peon are not worthy, not as a live
Emperor being at least.
Perhaps we should try something… Dart of control
rune of might crossbow
different.
master crossbow Who knows when, who knows where, all
Deathmarker you know is one is enough if it’s Lucky target
rune of focus correctly directed.
master crossbow Once the wheel has started turning, it
Bloodrain can only accelerate. Nothing can stop it Shadow dance
rune of insanity but satiety.
master lance Long arm of You may pass, but be sure that what
awaits you at the other side will not be Prison
rune of justice law better.
master lance Persistence is the key. Mountains don’t
Butcher fall in one day, but once they do they Final leap
rune of momentum bury entire nations.
master lance Strong enough to hold a fallen tree,
Glorious
Pillar of truth strong enough to hold a giant, strong
rune of purity enough to hold an army. persistence
master staff Royalty does not dirty their hands. Why
Emperor staff should they? Test subject
blessing of might
master staff Distance won’t save you know, for the
Naivety further you are, the higher you’ll fall. Trail of powder
blessing of insanity
master staff Once doomed, forever doomed. Let the
Despair condemned ones fall. Requiem
blessing of darkness
master wand Deceives enemy’s mind by setting tricks
Deceiver and traps on him, directing it to the Spell agents
blessing of focus grand finale.
master wand Not only knowledge will grant you
blessing of Discipline power. True power often resides in Big bolt
mastering the basics.
momentum
master wand Frees the souls from its mistakes and Faith
Baptizer lets the body start again.
blessing of purity resurrection
master tome No one will run away, no one will elude
Armageddon the pain. They will all suffer the torture Ambush
blessing of lethality of impotence.
master tome
Sentence Sinners don’t deserve dying by my hand Distant law
blessing of justice
master tome Power hungry, it will dispose the chaos
Gluttony in its very primal form… If you can afford Power hunger
blessing of greed its cost

master
axe/knife/sword Half-moon shaped blade that can act
Warglaive both as a sword and as a bow. Dual ammo
master
bow/crossbow/lance
master
axe/knife/sword Ethereal dagger that allows multiple
Arcane blade copies of itself and can be summoned Juggler
master almost everywhere
staff/wand/tome
master
bow/crossbow/lance Wand and There is no mix at all, you are just
wielding a crossbow in one hand and a Dual wielding
master crossbow wand in the other! Where’s my axe!?
staff/wand/tome

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Iron and Time – Weapons Roger Rodríguez Camprubi

RANK 3 to RANK 4
Harvester The physical concept of an
Judicator Vähendama axe, nothing will stand, the
Axecallibur swing of Vähendama.
Razor whip The physical concept of a
Scalpel Löikama knife, there are no places
Melter Löikama doesn’t sneak into.
Oratie The physical concept of a
Blackhowl Mööka sword, nothing lasts more
Emperor sword than the will of Mööka.
Driller The physical concept of a
Mistwhisper bow, if it exists it can be hit,
Kummardus
if it does not, Kummardus
Shadowspark
will hit it anyway
Emperor crossbow The physical concept of a
Deathmarker crossbow, be ready for a
Kahurikuul long corpse check, for
Bloodrain Kahurikuul leaves no
witness.
Long arm or law The physical concept of a
Butcher lance, one can easily forget
Tokama
the physics matter if it relies
Pillar of truth
in Tokama’s prominence.
Emperor staff The physical concept of a
Naivety staff, born a thousand times
Väntel
from within the land, Väntel
Despair
will rise again.
Deceiver The physical concept of a
Discipline wand, magic seems
Völukepp
powerless when consumed
Baptizer
by Völukepp’s might.
Armageddon The physical concept of a
Sentence tome, despite the power it
Arveraamat
emanates all pages of
Gluttony
Arveraamat are empty.
Warglaive We are restricted by rules,
Arcane blade by limits, by bounds…
Kimäär
Kimäär is not. Power has no
Wand and crossbow
limits.

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Iron and Time – Weapons Roger Rodríguez Camprubi

RANK 4 to RANK 5
Vähendama Axe of a
Kapten Vähendama Whirlwind
Primal fragment worldbuilder
Löikama Knife of a
Kapten Löikama Entropy
Primal fragment worldbuilder
Mööka Sword of a
Kapten Mööka Hero
Primal fragment worldbuilder
Kummardus Bow of a
Kapten Kummardus Iron rain
Primal fragment worldbuilder
Kahurikuul Crossbow of a
Kapten Kahurikuul Serpent shot
Primal fragment worldbuilder
Tokama Lance of a
Kapten Tokama Impaling army
Primal fragment worldbuilder
Väntel Staff of a
Kapten Väntel Black hole
Primal fragment worldbuilder
Völukepp Wand of a
Kapten Völukepp Wingardium
Primal fragment worldbuilder
Arveraamat Tome of a
Kapten Arveraamat Hiatus
Primal fragment worldbuilder
Kimäär Weapon of a
Kapten Kimäär Mitosis
Primal fragment worldbuilder

24
Iron and Time – Abilities Roger Rodríguez Camprubi

Full strike: Performs a full strike with your melee weapon, dealing damage in a cone.
Charged shot: Throws a huge projectile in a straight line that damages all units.
Magic blast: After a short delay it blasts an area of ground with magic energy, dealing damage to all enemies within.
Meteoric jump: Jumps to a near position and deals damage around you.
Shadow step: Passively increases your movement speed by 20%, activate to teleport next to an enemy.
Quick dash: Dashes to a nearby position dealing damage to all enemies around, this ability has 2 charges.
Rapid fire: Increases movement speed by 100% and continuously shoots projectiles to cursor position for a duration.
Landmark: Shoots a landmark to a position, activating the same ability on a landmark will, instead, move you there.
Shove: Pushes backwards all enemies in a cone, deals them damage and throws you backwards a little distance.
Timestamp: Drastically slows time for a duration for everything but you.
Teleport: It creates a space anomaly in a near position and teleports to it. Space anomalies will do ticking damage to all nearby enemies and
explode after a duration.
Combustion: Turns you into pure energy, tripling your movement speed and causing you to deal damage to all enemies nearby for the
duration.
Counterattack: When activated it reduces the damage from the next attack received within 3 second a 60%. After 3 successful blocks, the
next ‘1’ damage is doubled.
Glorious persistence: When activated it will start building fury as you get hit, once 100 fury have been reached your next ‘2’ ability will deal
massive damage and push farther.
Faith resurrection: Uses mana to restore all hp as a shield, when the shield is broken it deals damage to all enemies who attacked it. Re-
activating it consumes the shield and grants your ‘1’ and ‘2’ abilities a 1-use damage bonus equal to the amount of health left when
consumed.
Nomination: It selects 3 random enemies, teleports them to random locations and freezes them for 10 seconds. If you successfully hit any
of them while being frozen with Full strike, you will nominate it knight and will empower its strengths, helping you in combat for 20
seconds.
Dart of control: 2 charges. When activated throws a dart at an enemy and makes it battle for you while it loses hp. Hitting it with Charged
shot will throw darts to all directions. Using Landmark on it will act as an ordinary landmark and additionally heal the controlled mob.
Test subject: Takes control of a weak enemy and makes it battle for you and will drain its hp over time (if possessed with 100%hp it should
last 15 seconds. Casting Magic blast on the test subject will consume 30% of its hp and ignite it, causing it deal damage to all nearby
enemies. When a test subject dies you can either use Timestamp to resurrect it or Magic blast on it to make it explode, dealing moderate
damage in a big area.
Heavy metal: Generates fury more quickly. Activating will consume all your current fury and give you a bonus of x*3 on your abilities range
and x*1.5 on your abilities damage where x is the % of fury spent. It lasts 10 seconds
Overly sized projectile: First activation will start consuming clarity and charge a projectile over a location. The more you charge, the most
area will it cover and the most damage will deal. Second activation will stop the drain and will shoot the projectile. Running out of clarity
will cause your projectile to disappear.
Power hunger: First activation will start consuming mana, second activation will stop the mana drain and grant you a buff to all your
damage proportional to the amount of mana consumed that will last 10 seconds.
Charge: Each successful Full strike will refund its fury cost and reduce 10% its cooldown up to a max of 50%. After 5 successful Full strikes
you can activate this ability to charge against your cursor location rapidly, doing damage to all nearby enemies.
Final leap: Each successful Charged shot will increase your movement speed by 20% up to 100%. After 5 successful Charged shots you can
activate this ability 2 times to jump to a position and deal damage to all nearby enemies.
Big bolt: Each successful Magic Blast will increase its range by 20% up to 100%. After 5 successful Magic blasts you can activate this ability
to cast a big bolt in an ultra-wide straight line.
Blood boiler: Your Shadow step grants you 20 fury, applies hemorrhage (deals little damage and creates a blood pool every second for 10
seconds) on the enemy and is usable 2 more times during 3 seconds after the first activation. Activating this ability will cause all blood to
boil, dealing damage to all nearby enemies in a small range.
Execution post: After a brief cast, a wooden post spawns at a distant location. Your Charged shot will now repel all enemies hit for a large
distance, but it will have its cooldown drastically increased. If enemies repelled bump into the post they receive great damage and get
stunned for 3 seconds. Autoattacks will decrease the cooldown of Charged shot.
Ambush: (passive) Your Magic blast now leaves a fire zone that massively slows and deals damage to enemies inside. It disappears after 20
seconds. (active) Creates a wing gust in a cone direction that deals damage and pushes enemies back, if it hits a fire zone it expands the
zone in a large cone.
Blade storm: On activation it starts draining fury (with full fury it lasts 10 seconds). While active, your Full strike costs no fury and spawns 5
mad blades. Your Shadow step also spawns 3 mad blades. Mad blades travel a distance, dealing little damage to every enemy hit, when
they reach their end, they turn back and travel another line in a similar direction but opposed way and then they repeat for a total of 3
travels.
Shadow dance: On activation it starts draining clarity, shooting a dart in a random direction every 3 clarity drained. It will start to drain
faster and faster over time until you run out of clarity. Going through a Landmark while active will consume it and restore a great amount of
clarity.
Trail of powder: Activating this ability on an enemy will set a pile of powder under it and a detonating fuse under you. It can be activated
more times, each one costing more mana and dealing more damage. Landing a Magic blast on the detonating fuse will ignite the line and
will start exploding each pile. If the explosion deals damage to a marked enemy, you’ll restore its mana cost.

25
Iron and Time – Abilities Roger Rodríguez Camprubi
Wallbreaker: Summons a wall at a position. Striking the wall with Full strike will break 1/3 of it and shoot rocks in a straight line.
Prison: Creates a small post on the selected location. If a Charged shot strikes two posts it will create a line of energy that unites them.
Enemies that cross the line will receive moderate damage.
Distant law: Creates a runic circle in a marked position, slowing all the nearby enemies. Using Magic blast on the circle will cause it to
activate and will start dealing damage to all nearby enemies. Driving through in Combustion form will consume the circle and shoot you a
medium distance dealing great damage to all enemies hit and pushing them away.
Surgery: When you use Shadow step on an enemy you mark it with 1 stack of ‘open wounds’, next time you successfully strike it with Full
strike it will gain a charge and you will apply 1 stack of ‘open wounds’ to two more enemies. Activating the ability deals damage to every
marked enemy depending on the amount of stacks it has.
Lucky target: When activated, a target will spawn in a random location and will stay active for 2 seconds before disappearing. If the target is
hit by Charged shot it grant you ‘safe spot’ buff, resetting the cooldown of Charged shot and increasing its range, wideness and damage for
3 uses.
Spell agents: (passive) Your Magic Blast also creates a space anomaly in its position. (active) Cast an arcane missile that travels in a straight
line, every space anomaly cast a copy of the same missile directed to the same point.
Dark pact: Curses an enemy with a hex, which deals him damage over time and generates you fury every time it deals damage. Striking the
enemy with Quick dash will transmit the hex to all enemies dashed afterwards. Whenever you are at 100 fury you increase your damage but
also receive damage over time. When a cursed enemy dies you restore a portion of your health.
Infection: Marks an enemy with poison, dealing it damage over time and draining your clarity. When the enemy dies, poison is transferred
to another enemy. If the enemy is hit with Charged shot it will infect another enemy.
Requiem: Marks an enemy with a 15 charges Requiem debuff. Each second you will lose 5% your mana and drop one charge of that
requiem debuff (if you have no mana, no charges will drop). Additionally, every time you deal damage to a marked enemy it will lose 1
charge. Once the debuff reaches 0 charges the enemy explodes, receiving massive damage and dealing great damage to all nearby enemies.
(This ability has nearly no cooldown).
Dual ammo: Switches between ranged mode or melee mode, changing the autoattacks range and your ‘1’ ability. Each melee hit or ability
stacks ‘distance bonus’, and every ranged hit or ability stacks ‘proximity bonus’. This bonuses will apply to the first ‘1’ ability used when
switched form.
Juggler: Each ‘1’ ability you use will spawn a spectral knife. Activating the ability makes all spawned knives rush to a position or target,
damaging everything in between and dealing damage in area at the arrival point.
Dual wielding: Every ‘1’ and ‘2’ abilities perform at the same time a wand and a crossbow ‘1’ and ‘2’ abilities. Activating will start summon a
space anomaly on a landmark. Once the charge has finished, the orb will start shooting the arrows at random enemies. Lasts for 10 seconds
Whirlwind: Starts spinning for 5 seconds, attracting all enemies to the player, reducing the amount of damage received drastically during
duration and dealing them great damage while you are spinning.
Entropy: During 3 seconds you teleport to random enemies every 0.3 sec and applies them a mark of the mist master. 2 seconds after the
ability finishes. All marks explode dealing damage to every nearby enemy.
Hero: Transforms you into a giant and enhances the performance of your abilities. Reducing cooldowns on Full strike and Quick dash
drastically while increasing all your damage.
Iron rain: shoots a barrage of arrows to the sky. After 3 seconds, every enemy will receive 2-5 arrows (one every half a second).
Serpent shot: Throws a bunch of arrows. Each one of them attempting to hit half the enemies in combat, striking them one after another.
Impaling army: Spawns a great number of lance-soldiers. They travel from bottom to top of the screen dealing damage to every enemy hit.
Black hole: Creates 5 black holes in random location that absorb the enemies as well as their health.
Wingardium: Throws all enemies to a specific location, dealing them damage depending on the amount of enemies.
Hiatus: All enemies are suspended for 5 seconds. After this time each one fall and receive massive damage.
Mitosis: Strikes every enemy, killing it and spawning three minions for every killed enemy, setting a minions life on a 20% of its ‘father’
remaining health.

26
Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

3.b – Technology
Before talking about technology let’s first introduce the concept of Game Engine.
This information is very well known and very well documented across the net, so we will keep it
very simple here:

A game engine is a software framework that performs as a middleware for game developers,
enabling them to focus on the actual game scripting rather than physics, graphic rendering,
audio playing and many other features.

Their use became popular early 2000’s. Since then, the complexity of the games was not high
enough to justify an entire software framework development.
They were initially perceived mostly as a one-use software, limiting its functionalities to the
needs of the targeted game.
As time passed, and complexity in videogame programming raised, their initial concept changed,
and now a company usually owned their own rendering engine, and add up some other
functionalities depending on the specific targeted game.

Nowadays, the scenario is very diverse, and while some games still “require” a brand new game
engine, most of them can recycle tools, to the extent that some Game Engines has been released
to the market as a generic purpose game engine, often giving access to source code to adapt it
to the games that require it.

3.b.i – Epic Games and Unreal Engine

Epic Games is an American video game development company. Founded in 1991 under the
name of “Potomac Computer Systems”, they get themselves to know after the release of the
ANSI-based game ZZT that same year. During ZTT’s life span time the company became known
as Epic MegaGames.
During several years, the company released numerous
popular shareware games, and it was until 1998, after the
acquirement of Safari Software, that they launched Unreal,
a 3D 3th FPS (first person shooter) developed with the very
first Unreal Engine. From then on they kept up with the
series and released various Unreal games.
After officially changing the company name to Epic Games
in 1999, they released their best seller game, Gears of War,
in 2006, which was expanded afterwards with Gears of War
2 (2008) and Gears of War 3 (2011).
Game-wise their subsidiary studio chAIR, released Infinity
Blade (2010) for iOS devices and Fortnite (2011).
In July 2012, Chinese company Tencent Holdings acquired about 40% of Epic Games, and soon
after in the same year some of the most known names of the company, like the Gears of War
lead design director Cliff Bleszinski, left it. Some of their subsidiaries closed soon after too, and
their bestselling series license Gears of War was sold to Microsoft.
Recently they released Unreal Tournament, the continuation of their Unreal Tournament series,
and focused on enabling the community to mod the game as much as they could so it would
become a game made by players for player.
They are also expected to release Paragon during first half of 2016.
Obviously we wouldn’t be talking that much about them if they were the creators of the engine
used in this project: UNREAL ENGINE. Let’s have a brief look on its history:

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

As mentioned, the first version of the engine was released with the name that give it its name
in 1998, and it immediately became available for external studios under a Proprietary license.
November 2000 bring with it the last stable version of the engine along with the first Unreal
Tournament. This version was programmed in C++, Assembly and
UnrealScript. This last, along with the modularity of its architecture
and the cross-platform feature, made the engine very popular, and
quickly started to be designed in a way to be extensible and improved
over various generations of games.

Unreal Engine 2 was released early-2001, it was written in C++ and

assembly and it included Nintendo’s Game Cube, Sony’s Play Station 2
and Microsoft’s X-Box as developing platforms. One of the most well-
known games developed with UE2 is Killing floor.

Unreal Engine 3 was released March 2004, and it settled a breakpoint in the way the industry
understands game engines. Big companies that would have built their own engine, started
developing with UE3, and huge titles like Bioshock Infinite were launched under the flag of
Unreal Engine.

Epic Games released in 2009 a free (for non-commercial use) version of the current UE3’s SDK
under the name of Unreal Dev Kit. UE3 was built to be heavily modded, and releasing a free copy
of its SDK turned into what was the next logic step:

Unreal Engine 4 was shown to the masses during GDC (Game Dev Conference) 2012, with an
impressive demo that was thought to be a cinematic until Epic Games demonstrated it was
actual gameplay footage.
It wasn’t until 2014 that Unreal Engine 4 was released under a subscription fee + 5% of gross
revenue resulting from any commercial use of products built using UE4. The engine improved
greatly in real-time global illumination, and it left the Unreal Script that featured all the older
engines to introduce Blueprint Scripting, a visual scripting system that uses C++ and enables for
live debugging, making it the ultimate tool for prototyping.
A year later, in March 2015, Unreal Engine became available for everyone for free along with all
its future updates, with the only cost of a selective royalty schedule.

Unreal Engine 4 has become a very powerful source both for indie and professional
development, being a great choice to begin but also a powerful engine for AAA games.
Prove of it is all the awards it has received. After being announced and even way before its
launch, it received 3 awards: “Best Taste of Next-Gen” by GamesRadar, “Coolest Tech” by IGN,
and “Best Tech” by Game Informer. After its launch it was awarded with “Best Game Engine” by
both Develop Industry Excellence Awards and Develop 100: The Tech List.
Along with them, UE4 entered the Guinness World Record as “Most Successful Videogame
Engine” in its release year, 2014.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

3.b.ii – Unreal Engine’s blueprint technology

This project was built using UE4’s blueprint technology, we’ll get deeper in the “what” in a
moment, but let’s first explain “why”.
Initially, the intention was to build the project in full C++, although being far from decent at
programming in this language, I was in disposition to take the challenge, so it is one of those
things I’ll have to learn sooner or later.
Before starting to code I needed to learn the engine, and I decided to start with one of the
excellent-quality tutorials Unreal Engine has in its Youtube channel.
It was about getting started at UE4, developing a very simple project with blueprints. It took
about 2 hours to complete the tutorial, and by the end of it I was completely sure that that was
the way to go.
I’m not saying that blueprints are better in any way than C++ pure coding, they simply serve
different purposes. While C++ will always be solider and easier to manage in a programming
team, Blueprints are very good for prototypes and one-man scripting. They are great for getting
things done quickly and in an easier-to-understand way and, more importantly for this case, they
are a perfect tool for learning the engine.
I’m now convinced that my next project will be in C++ traditional coding, but I wouldn’t change
bugs) aside, I think the results speak for themselves.

Now let’s get into what they are, and there’s nobody who can define them better than Unreal
Engine themselves:
The Blueprints Visual Scripting system in Unreal Engine is a complete gameplay
scripting system based on the concept of using a node-based interface to create
gameplay elements from within Unreal Editor. This system is extremely flexible
and powerful as it provides the ability for designers to use virtually the full range
of concepts and tools generally only available to programmers.

Unreal Engine 4 Documentation - Blueprints Visual Scripting

There we have it, Blueprints are basically a visual scripting method with C++ working at its core.
Now, it wouldn’t make much sense if we tried to explain a visual system without visual support,
so here is a picture of what a blueprint looks like in the editor.

Figure 1: Blueprint overview in UE4 editor

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

That is far too small to get anything from it, so let’s expand it to sections. They are ordered in
the most understandable way rather than the typical ascendent order.

1. Viewport and components: First thing I think should be pointed out is how we must think
about a blueprint. While there are “special” blueprint types we’ll see later, we should think
about a blueprint as a full entitny. It can have
its materials, models or textures and its
behaviour. Pretty much everything we
develop is a blueprint with some
components in it, and thats what this part
covers.
The components menu (figure 2) is active by
default in all the screens in the blueprint. But
we may modify the values with a grade of
knowledge over what we are actually doing,
thats why we use the viewport.
In the viewport (figure 3) we can visualize
which components we have in our
blueprints, and, we can modify its values
(think making a collider bigger or adjusting
the default rotation values). All these
components will be callable and modifiable Figure 2: Components window
through the graphs, as we’ll explain in a
moment.
6. Details: This section will change depending on what we have selected. It is the window that
presents de configuration of any node, variable, function,
components etc. and enables us to modify its values.

Figure 3: Viewport view Figure 4: Details window

4. Variables: As in any programming language, variables are information containers that

represent an attribute of the class (blueprint in this case). In blueprint scripting they are always
created with a default value, so they cannot be null (with the exception of references). Let’s take
a look at Figure 4 to understand them better.
Variable name and type are obvious.
Editable field enables or disables the modification of the variable through the UE4 scene editor,
and tooltip is the definition shown when hovering the field of this variable in the scene editor.
If expose of spawn is enabled, whenever I spawn an instance of this blueprint, I will be able to
initialize the value of this variables. We should think about it as “should this variable be passed
by parameter in the blueprint constructor?”
Finally private decides whether or not the value will be modifiable from other blueprints.

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3. Functions: We’ll get deeper into how graph-based programming works, but for now let’s put
the following example. I want to do the following using blueprints: Whenever I press “K”, I want
the blueprint to loop 10
times printing an integer
each time and increasing its
value by a random number
from 0 to the number itself.
We could do it in 3 different
ways:
a. Following the command
with its logic directly, as
shown in Figure 5.

Figure 5: Logic follow the command directly

b. Making the command call a custom event. Events are nodes that we can launch inside or
outside the blueprint. They reside in the main logic graph, the Events graph, and are usually used
to define one procedure. They can be passed in-parameters, but they don’t provide an output.

Figure 6: Custom event calls

By doing so, we can better control what exactly happens when we press “K” (we could be calling
a bunch of events at the same time, and this way we could easily see which ones). But this have
two weaknesses. By one hand, this “AuxInt” we are editing has to be a blueprint variable, for we
cannot create local variables in the Event Graph; by the other one, there can be no output.
Imagine we want to call this from a different blueprint and get the result: we should call the
event and then check the variable, which, by the way, could be private.
Events are great to define procedures and behaviors that heavily involve class attributes, but in
this case, the best solution would be to create a function.
c. By creating the function, we implement the logic in a different graph, which has local variables
available and can have multiple outputs, for example if the number if even or not:

Figure 7: Function Example

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

We will be now able to modify the behavior of this function in its own graph, with access to
multi-output and local variables.

Figure 8: Function example (UI)

2. Construction Script: Every blueprint has an Event Graph (which we already mentioned) and a
Construction Script. Now, what’s that? The construction script is a graph with one function that
will be called every time the blueprint is compiled, instanced or modified via editor.
To understand its usage, let me put an example directly from the game:
I have a blueprint called “weapon”. When I instance a weapon I don’t want to pass each and
every parameter (let’s suppose: resource, ability and level.). This would create a very poor
system that would need a lot of double-checking to ensure every parameter is correctly passed.
I don’t want to create a blueprint for every single neither. They would be easier to instance this
way, but it would overload my project with lots of files that don’t need to exist.
What do I do then?

Figure 9: Construction Script example

As we see in Figure 9, we use Construction Script to access a function in an external library in

runtime. This way we expose the variable ID to spawn, and since the very first thing done is the
call to the Construction Script when the blueprint is instanced, even before being flagged as a
valid object, the function is called and the output sets the attributes Resource, Ability and Level.

5. Event Dispatchers: Event Dispatchers come very handy during the implementation of the
level blueprint (which we’ll cover later). It enables you to raise a flag that any blueprint that
has an instance of this object will be able to listen. Again let’s put an example of this.
Let’s assume we have a friendly NPC who is speaking, and let’s assume that once she has
finished, she must move to a position. But how? Friendly NPC’s have methods for speaking and
moving but they are not related so, how? Well, as always there is more than one way.
We could create a variable “isSpeaking” in FriendlyNPC blueprint and check its value each frame.
While checking a condition is not very expensive (resource-wise), it only adds up and is definitely
something we can avoid.
We could instead create an event dispatcher and call it at the end of the Speaking Event. Then,
in the “caller” blueprint, we just bind an event to this dispatcher, and anytime the character
finishes speaking, this event will trigger. (Of course we can unbind the event whenever we want)

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Up to this point we’ve seen what the interface presents us before starting to script, but knowing
all this, how do we start, how do I program with nodes? Well, thing is it is easier than it seems.
Let’s have a look at some basic nodes:
Event BeginPlay: This event is the first one called when
a blueprint is spawn. It is always called (except if there
is no logic in it). It is usually used to initialize attribute
instances (for example, in an enemy’s Event BeginPlay
we will create and initialize the GUI blueprint for its
over-head health bar) and to get reference to
GameMode or PlayerCharacter. In most situations it is
better to initialize Boolean values like enabling input on
the actor here instead of the Construction Script.
Figure 10: BeginPlay Event node
Event Tick: This event is called every frame as long as the
instance of the blueprint is still valid. We can enable or disable
the ticking of an actor, but it isn’t recommended at all.
It gets Delta seconds as an input, which is the time (in seconds)
between this tick and the last one and it is used as a
multiplication factor to ensure a smooth gameplay with
irregular framerates.
Figure 11: Tick Event
We can follow up this events with logic or calls to other custom events. Our custom events will
be called either for one of this two mentioned nodes, by being called from another blueprint, by
trigger effects (like collisions) or by input command.

Now, input commands are simple to understand, you either press a button, turn a stick, release
a button etc. and some logic is called, but again, there are choices to be made in order to
implement them. We can implement it the simple way
by directly calling a key as shown in figure 12. That is very
useful for testing purposes for example, when you
quickly want to assign logic to keys. Also, it is used when
the key pressed is more important than the action itself
(for example a QTE (quick time event) where you are
Figure 12: Direct command input example
asked to press “P”, not because it means anything but
because it is further from your hands and therefore
harder to reach).
While this isn’t a bad way, UE4 offers a great action-
key mapping tool to improve input commands
(Figure 12). This way, we can have action “Jump” and
call it either by pressing Space Bar in a regular
keyboard or “A” button in an Xbox controller. Aside,
this way makes it easy to add modifiers such as shift
or Ctrl. In Iron and Time, spells can be casted by
pressing 1,2,3,4 or shift+left-click, shift+rc, ctrl+lc,
ctrl+rc.

Figure 14: InputAction call

Figure 13: Input Mappings

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

Now we know how events are called, but how are they structured? Let’s take a look at an
example.

Figure 15: Flow example

We see the implementation of “TestEvent”. This event will be called somehow (we don’t really
bother here), and once done, it will call the events “ExecuteTask1”, “ExecuteTask2” and
“ExecuteTask3” in this order. To do so we must connect the flow connector from the event into
the starting flow connector of the event we want to call as pointed with the red circles. Once a
node gets its call it will call all the logic used to get its values.
This is an important part of blueprint scripting: There are nodes that are flow conditioning (like
events, functions, setters, conditionals, loops etc.) and other that are flow contributes (getters,
value checks, variable calculations etc.).
In this example ExecuteTask1 calls a getter for Health Value (which is a blueprint attribute), if
ExecuteTask1 wasn’t called, this getter wouldn’t be neither.
ExecuteTask2 gets the GameHUDReference and checks if it is valid (the equivalent for Null or
None in other languages).
ExecuteTask3 creates an array of strings.

I found nothing as a blueprint organization agreement, so I decided that, whenever I could, I

would put the value nodes used by a node directly below it (as seen in the example).

Now, there are some modifiers that can alter the flow line.
Branch: It is the typical “if-else” of any other programming language, it
receives a Boolean as input parameter and whether it is true or false it
will execute one of the flow-output branches or the other. (Fig 16)

Figure 16: Branch example

Loops: As expected, we have loops functions in
blueprint scripting, aside from the two ‘for-loop’
forms in Fig 17, there’s also ‘while-loop’ nodes. They
receive an array or two integers as input and have
two flow-output pins. Loop Body will be the one that
will define the logic in each iteration, completed will
be the one called after the loop is finished. All very
obvious, but it’s easy to mess up and continue your
code in the loop body branch if you don’t pay
attention.

Figure 17: Loop example

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Flip Flop: Flip Flops are very useful when following input commands. They
when they are called, they follow up with the logic at branch A and ignore
branch B. The next time it is called it will call branch B and ignore A. This
comes handy in actions like “open inventory” where you want it to open
when you press the open Inventory command and to close it when you
press it again.
Figure 18:Flip-Flop

Sequence: Sequence nodes are very simple to understand, they call

all the logic connected to every branch one after another. In the
sequence node shown in Fig 19, branch “Then 0” would be called on
entering, then “Then 1” and finally “Then 2”.
This comes handy when you want to execute various independent
tasks with a simple call. It does not provide any functionality we
couldn’t achieve without it, but helps a lot at scripting cleanly.

Figure 19: Sequence

Gate: Gates are a little more complex than previous flow modifiers but are very useful in certain
situations. We should think about it as it name suggests, it is a gate that will enable the flow to
pass through or not. Let’s take a look at the example in Fig 20 to better understand what gates
do.
If Test Bool is true, we will attempt to enter the gate, since it is the first time the door will be
opened (as specified with Start Closed parameter), and we will call ExecuteTask1. After that, we
see that ExecuteTask1 follows with closing the gate (by connecting its out-pin with Gate’s Close
in-pin). Next time we access the branch node, if Test Bool is true we will attempt to enter the
gate, but it will be closed and we will have to stop here (so ExecuteTask1 won’t be called); if it is
false, we will open the gate again.
This allows us control over how many times a code section is called. By doing this, we are
ensuring that ExecuteTask1 will only be called the first time Test Bool is true after being false.

Figure 20: Gate example

And with that said we know the basics about blueprints. This was not intended to be a tutorial
nor a crash course, but to be a complete enough source to enable anyone with basic
programming knowledge to read blueprints and understand what is happening in an Event
Graph.

Although, as everything is organized in blueprints, it quickly becomes obvious that not all
blueprints fit in this scheme. We have now learned about the Blueprint class, which defines an
in-game actor element. All the other types of blueprint function similarly, but there are few
differences between them. In the next section we will talk about file types including all the used
blueprint types.

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

3.b.iii – Unreal Engine File types

Alright, we know the basis about blueprints, how do they work and how they are programmed,
but that is just a part of what programming a game is about. There are lots of other objects we
must manage.
A blueprint can represent a character, and it will integrate its physics with its behavior and the
relationship with the world and other actors. That means we must have components such as a
skeletal mesh, to give it a shape and enable animations, which is at the same time created by a
3D model, a skeleton and a group of materials which are a result of working with textures.
As you see, what a blueprint represents is a bunch of information blocks that create an entity
when grouped together, and, while some of them are already very well known, it is vital to
understand what kind of objects are available for us to us.
The best way to explore them is via the menu presented when trying to create a new object,
and this presents some types that I know and some others that I don’t or I haven’t used.

Animations:
Animations are the elements used to set
movement in a mesh, every movement a
character does is an animation (excluding
translation in space). While it is possible to
create animations in UE4, they usually are
imported from other specialized software
like 3DMax or Blender.
What UE4 does best is managing the
already created animations in the ways we
are about to describe.

From all the types in Fig 21, I didn’t use

and therefore, don’t know: Aim Offset,
Figure 21: Animation creation menu Aim Offset 1D and Paper Flipbook.

Animation Blueprints are a kind of animation that relates the skeletal mesh with the actions
defined in the blueprint containing it. All animations should be called from here through
(preferebly) state machines. Here are some screenshots to give an understanding.
As we see in Fig 22, the
animation state machine
for our main character
has 4 states: Locomotion,
whether he’s idling or
moving, Jump (although
we can’t actually jump in
game, we need an
animation to play when
falling or performing
some abilities), Shoot and
Attack. This are played
based on local variables in
the animation blueprint.
It has two main sections: Figure 22: AnimGraph state machine
the animGraph, where
state machines like this one are placed, with the rules to change from a state to another one,
and the EventGraph, which accesses the owning blueprint and contains the logic to properly set

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Design and Implementation of an A-RPG in UE4 Roger Rodríguez Camprubi

the variable that will be checked by the AnimGraph. It is possible to insert logic inside the
EventGraph of an animation blueprint, but it is only recommended if it’s the best way. For
example, we may want our attack to deal damage exactly at a certain point of an animation, so
we will implement an event EventDealDamage in the main blueprint and call it from the
animation blueprint EventGraph. Fig 23 shows an example of how the enemy AI blueprint does
that:
We first get the owner’s
blueprint with “Try Ger
Pawn Owner”.
When we receive a
notification that it is the
time to deal the damage
AnimNotify_AttackHere
(we’ll see later in this
section where these
notifications are created)
then we cast the owner
to the class we expect it
to be. If the cast is
successful we call the Figure 23: Anim Blueprint eventGraph shooting main blueprint's events
event “Attack” in
Melee_Bear’s blueprint. Te same happens with the death animation, when it has finished we
receive the notification and call a method in the main blueprint to destroy the actor.

Animation comosites are only a way of grouping various animations into a single one. It just
composites one after another.

Animation montages serve multiple and various purposes. With an animation composite you
get the result of an ordered composition of animations. But you cannot set breakpoints in the
middle, or start at a preferred
section. With a montage you can
set up, for example, a puching
sequence. You will always start
with a puch rising animation, but
from then, if you keep your input
active you want to strike with left
and right punches continuously
so you can define an entering
animation, then begin a new
section with left puch + right
puch. Whenever this section
ends, if the input is still active it
will restart, if it’s not it will jump
to another section with the
proper ending (either left or right
arm recolocation). This way you
can have a bunch of animations Figure 24: Animation montage example
that usually go together in the same object and it enables you to play it in a custom way, not
necessarily one after another and repeat.
Additionally you can play sounds at given points of the montage, play particleFX, shoot
notifications (that can be listened in the EventGraph as explained before) etc.

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Blendspace/Blendspace1D: A blendspace is an animation the behavior of which is altered

depending on a variable. The most common
example is the locomotion animation.
Assuming we have an IDLE animation, a WALK
animation and a RUN animation we can create
a blendspace with them and the variable
speed. When speed is 0, IDLE will be played,
when it’s 80, WALK will be played and when its
200+ RUN will be played. Any number in
between will create an animation blend
between its two nearest animations. For
example, if the speed is 120, the animation
played will be a mix with WALK and RUN.
The example described is a Blendspace1D, Figure 25: Blendspace example
because the result animation only depends from 1 variable. You can create an n-D blandspace
where your animations depend on multiple factors, but it becomes too complex quickly.
This system is amazing to give animations a smooth feeling.

Blueprints:
We covered Blueprint classes in a previous
section, and, as we said, there are more
types of blueprint that share similarities
with it. We’ve seen the animation
blueprint in the animations section, but
there are other logic-centered blueprints
aside from Blueprint class.
As we already know Blueprint Classes are
used to define an in-game element, with
its components, its viewport and its logic.
Blueprint Function Libraries Are
blueprints without an EventGraph, they
Figure 26: Blueprint creation menu only contain functions which can be called
from every other blueprint without any need of an instance (in fact, they cannot be instanced).
In the game, I use a blueprint function library to access to database. Every time a blueprint needs
an access to a table it calls a function in this library and it is the function the one who generates
the “queries” and returns the result.
Blueprint Interfaces are interfaces as known in Java. They contain methods without its
implementation and it’s up to the classes that implement the interface to define a specific one.
Its usage is the same as any other programming language, we can check for actors in-game
containing a specific interface and call its methods seamlessly without bothering if they have
the same implementation or not.
I did not use Blueprint Macro Libraries, but they are used to store frequently used node
sequences, to save time if there are lots of blueprints that implement them.
Enumerations are used to define a closed group of states. For example, a switch can be ON or
OFF and we can implement that with a Boolean, but what happens if it can also be half-pressed?
We can create an enumeration with the fields [OFF, HALF, FULL] to cover that. They come very
handy to define state machines for example.
Structures are C and C++ typical structs. A single object containing various variables of various
types. For example, Weapon struct contains an enum “Resource” to decide whether it will use
mana, fury, clarity or chaos, an Ability Base class reference “Ability” to indicate which is this
weapon’s specific ability and an integer “Level” to indicate which rank this weapon is.

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Materials and Textures

I got all my artistic assets from external
sources so that’s not really my field. Even
though, there are a couple of things I
needed to work with, and those are
Materials and Material instances.
Materials are the objects that decide the
final color on the objects they are applied
on. They save information about how is the
texture on it and how does it relate with
light, this way we can have a shiny but non
reflective wood based textured material
that stands for wood or a very transparent,
and very reflective blueish textured material
that stands for water. They are created and
modified in a graph based scripting
Figure 27: Materials and Textures creation menu environment (the Material Editor).
To keep it simple, a material instance is a copy of a given material (it is created from a material)
and can be used to modify some of its values. For example, let’s say I want some leaves to be
green and some others to be yellow. I don’t need to create two copies of a material, instead I
create what would be the parent material and 2 material instances, one for green and one for
yellow, and modify the only parameter that varies. This way less resources are wasted, as the
instances only save the changed information relative to its material.

Sound
Unfortunately, I had to stop the development
before reaching the point in which sound was
added. I was leaving it for the final part, and due
to this I’m not familiar with any of the types
available.
I intended to add voice acting and music
composition done by myself to the game if I had
been fine on schedule, but none of that has
been possible.

Figure 28: Sound creation menu

Physics only contain the type “Physic material” which enables a material to store some
information about the way it should interact with the world (such as weight, bounce ability etc.)

Figure 29: Physics creation menu

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User interface
At this point, I assume there is no need
to define what a user interface is.
In games they usually have a very
important artistic consideration, and
that is the reason unreal has its objects
to define the design of a GUI.
Fonts are obviously custom fonts.
Slate Brushes define how background
UI elements will be, can define a color
palette along with other useful
features.
Slate Widget Styles can define styles
Figure 30: User interface creation menu for buttons, text blocks, check boxes,
progress bars etc.

Widget Blueprints are the last type of blueprints left. First, instead of a viewport, it offers a 2D
space to draw the desired UI as shown in Fig 31.

Figure 31: Widgets blueprint edition interface

There are 5 main sections in the interface. The top-left one contains all the elements we can add
to the UI, both default and custom generated ones. Below that there is the hierarchy window,
containing all the elements in the UI and its relation (which one contains what). The central part
is obviously a preview of the design we (in the example in the figure it is the character interface),
we can drag the components here and modify its size.
The right section is the details panel, and it will change depending on what we have selected to
modify its values.
Finally the section below is the Animation window, you can create animations in widgets by
modifying almost all of its values. In the example there are no animations in this UI, but if you
check the pause interface you’ll find a couple.
Widget blueprints have its own EventGraph, which, like the EventGraph in animation blueprints,
can access the owner’s attributes. As opposed to animation blueprints though, widget blueprints
use to have lots of logic in their graphs. (The whole interaction with the inventory and the forge
is done via interface, so aside from the core forging mechanic, all the logic related to these is in
the character’s interface widget blueprint EventGraph. Just as a curiosity, let’s see how much

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logic is in there graphically:

Figure 32: Character Interface EventGraph

Aside from this graph there are lots of functions in this widget, making it presumably the most
logic-heavy class in the project (if we don’t add up the parents’ logic to the children classes. In
this case it would probably be some abilities). We can bind values in the UI (such as the health
value) directly to a variable in the character or bind them via functions in case some calculations
must be made.

Miscellaneous
Miscellaneous contains a lot of diverse types, and from
all of this I have only used one: Data table.
They are just that, data tables created from a struct. You
can create entries and set their values. Theoretically
they can be imported from and exported to Microsoft
Excel, but that didn’t really work when I tried, resulting
in a huge loss of time. I’ll explain later why exactly I use
them and how many there are, but at a basic level, you
can access a row with its name or by iterating on the
table and get its values. The following figure shows as a
very little portion of the combination table.

Figure 33: Miscellaneous menu

Figure 34: Combination table fragment

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Blendables, Paper2D and Artificial Intelligence

Figure 35: Other types

Regarding to Blendables and Paper2D, I did not use them (aside from what we’ve told about
materials and mat. Instances).
And regardings to Artificial Intelligence, I actually did a tutorial and learnt the basics about how
Blackboards and behaviour trees work, but I decided not to implement it in the project, as the
AI I had built worked well enough, and there were still plenty of things to do.
As I did not use them, they won’t be covered, but at a very simple level they are a way to
structure AI in a tree-like way, with state machines integrated in the class blueprint and actions
linked to them.

Particle Systems are combinations of particle effects, they can both be attatched to a blueprint
class via component or played at will from any blueprint.
Unreal Engine 4 offers a very powerful ParticleFX editor which I had to use to modify some assets
in order for them to better fit the game.

Levels are the objects containing all the information about a level. That includes the scene
with all its components (lights, actors already in scene, architecture, landscape etc.).
Levels contain the level blueprint, which is the one controlling the plot. How a level blueprint
differs from class blueprints and how it is programmed will be coverd in its own section later.

There are also some object types we’ll use but are not possible to create:
Static mesh: is a 3D model with its materials assigned. It has no skeleton and therefore, no
animations.
Skeletal mesh: It is a 3D model with skeleton. It does not need to have animations associated
but it must have at least one bone. (weapons, for example, need to be skeletal meshes instead
of static because they need a bone to assign as a grip).
Texture: Textures are 2D images. They usually are used as a part of the material creation process
or applied on 3D models direcly (auto-generating a material), but they are also used as raw
images in HUD-design and in-game thumbnails and icons.

As you may have noticed, every object type has a color assigned to easily differentiate it from
other elements when browsing the project. Thus we have blueprints, particle systems,
materials, animations, animation blueprints or levels.

With everything said, we know enough about Unreal Engine 4 to explore the project itself, see
how things are done and understand how it all commutes to create Iron and Time.

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4 - DESIGN

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4.a – Project Structure

We won’t be covering specific code sections, but we’ll try to get deeper into the project to
understand not only how a project like this would be made using blueprint scripting (all the
previous section), but how this specific game has been organized.
Which are its classes? What are they for?
Let’s start with an overview of the content folder:
Most of the folders here are asset directories
that don’t contain any worth mentioning
information.
Unreal Engine 4 has a still improvable but yet
very good reference manager. With this tool you
can select an item and see all the references to
other files. I planned on using that at the end of
the project to clear the huge amount of unused
assets I have, but, again, that was not possible.
Let’s explain which folder contains what though.

+150fantasy_icon_pack is an icon bundle I

bought from the Epic Games Marketplace. I
managed to get all the item thumbnails for the
items and the weapons from other sources, but
Figure 36: Content folder overview I was not satisfied with what I was finding for the
abilities thumbnails, so, as this pack was on sale,
I decided to use it for this purpose.

Geometry is almost empty and only contains a floor template and a couple of different size
cubes to be used as a size reference.

InfinityBladeAdversaries Epic Games released for free all the assets of the first Infinity Blade
game (iOS) September 10 2015. Unfortunately most models came without animations, and they
removed the SoundFX and Music packs from the store due to some copyright issues. Even
though, it still meant a great source of assets. This specific package contains a lot of models
(some containing animations) of Enemies used in Infinity Blade. I ended up just using one, but
have plans to put almost all of them in the game once I’m able to continue.

InfinityBladeEffects has been my main source of ParticleFX. Although I’ve tried not to reference
anything directly (I copied the effect to my own PFX folder and modified there) there may be
still some references to this folder.

InfinityBladeGrassLands is the package that contains all the level-construction assets. From
foliage to rocks, runes or statues. The final version is also planned to have InfinityBladeFireLands
and InfinityBladeIceLands.

InfinityBladeWeapons contains the skeletal meshes for almost all weapons in the game (there
was no bow, crossbow, lance and tome, so I had to find them separately)

ItemModels is a self-created folder to store all the static meshes and skeletal meshes for all the
items and weapons. Every item or weapon reference in a blueprint should point this folder
instead of InfinityBladeWeapons or others.

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MannequinCharacter stores the information about the default UnrealEngine4 character mesh
(the mannequin). I don’t use it at all in the current version.

Materials contain some materials I modified or created, for example

“enemy_selected_material” is the material applied on an enemy when you mouse over it.

MixamoAnimPack is a package of characters available free at the Epic Marketplace. It contains

a handful of fully animated characters, which include the main character model and the only
friendly NPC implemented model.

Particles contains all the ParticleFX used in the game, most of which are copies from PFX in
InfinityBladeEffects and have been directly implemented into the game or modified to better fit
the fantasy.

StarterContent is the folder that is included by default in all UnrealEngine4 projects. It contains
a little bit of everything, from basic shapes and textures to some materials. I don’t use it a lot,
but some of the materials in there have come very handy to create the levels and modify item’s
materials.

Thumbnails contains all the icons of the game, split into items, abilities and weapons, as shown
in Fig 37.

Figure 37: Thumbnails folder

TopDownBP is where all the blueprints, data tables, structs, levels etc. are saved. It is the only
folder containing logic, and we’ll explore its content in the next section.

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4.a.i – Classes structure

TopDownBP folder contains all the blueprint classes and therefore all the logic. There is no thing
as a classes’ diagram, but there are some hierarchies and package options that are worth
mentioning.
We’ll take Fig 38 as an Index Reference, and explore
each folder and subfolders explaining whatever
they have inside. Before entering let’s observe it is
divided in two main folders: Blueprints, that contain
all the blueprint classes, data and logics and Maps,
that contains the only level we currently have.
We’ll start with Blueprints because we’ll link Maps
with the next section.

Figure 38: TopDownBP folder's content

Figure 39: TopDownBP/Blueprints

Blueprints contains two very important blueprint classes and 6 subfolders. The blueprints are:
 IATGameMode: Game Modes are a kind of class blueprints that perform as a game
launcher. You can add logic to it, but at its very core, it is class storing all the variables
that defines how the game starts. More precisely, it is responsible for setting:
o Default Pawn Class: the blueprint class of the main character.
o HUD Class: the widget blueprint with the main HUD.
o Player Controller class: The input source listener class.
Apart from these, it also controls Spectator class, Replay Spectator Player Controller
class, Player state class and Game State Class, but these are auto-generated classes that
I haven’t faced the need to work with.
GameMode blueprints can be accessed from everywhere, so they are a great class to be
used as a controller and to store simple values that must be accessible from lots of
different blueprints.
Aside from being the launcher class, in IaT the class controls the SystemHUD, which only
consists on the descriptor. As you will be told later, the current version is only playable
by removing the description class due to the bug, so that’s not something visible right
now, despite it was implemented in earlier versions.

 MouseController: It is the controller class. Like IATGameMode, each game must have,
at least one controller blueprint class. Its function is to capture the inputs mainly, but it
is also responsible of the pause menu, since pause is not something tied to the character
but to the player instead.
Aside from that, MouseController contains a bunch of testing-oriented methods, like
spawning items or enemies, fulfilling the resource bar or killing all enemies.

Blueprints folder has this subfolders:

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ABILITIES:

Figure 40:TopDownBP/Blueprints/Abilities

This package contains all the logic regarding the abilities. Since there are a lot of classes we will
only cover the ones that introduce curious techniques or are relevant to understand other
concepts.
 AbilityBase is the parent class for all abilities. To better understand it we must know
how an ability is defined.
All abilities have the following attributes:
o ID – used to retrieve the values from the database.
o Thumbnail
o Level – whether the ability is rank 1, 2, 3 or 5.
o Cost – its resource cost.
o Charges – how many times in a row can we activate the ability (usually one).
o Cooldown – how much time it takes to restore a charge.
o Duration – Used by certain abilities to determine how long the ability is active.
o Damage – damage the ability deals to an enemy
o Area – Used by certain abilities to determine the size of the effect
o Range – Used by certain abilities to determine the range covered by its effect.
With that clear, AbilityBase manages charges, cooldowns and costs for all abilities, and
has a method “PerformAbility” that all children classes must override. It also implements
the method canPerformAbility, that will be called by the child classes to check whether
they can be activated or not. (is in cooldown, insufficient resources…)
It presents the following problem: If both parent and child have an EventTick, which one
should be called? The only one called is the children one, so it is a good practice for the
parent class encapsulate all the logic that must be called each frame in a function (say:
PartentTick) and call that function from the child’s EventTick.

 All the other classes in the package are specific abilities implementation, there are a
couple of things several blueprints have in common:
o They get the 2D screen mouse position converted to a 3D world coordinate (as
shown in Fig 41) and play with its values to either shoot a projectile towards
that position, teleport there etc.

Figure 41: Getting the 3D world coordinate from the mouse position
o They do their damage via a generated item that damages enemies on collision
(for example a projectile).

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Additionally, TimeStamp uses an UE4 function called SetGlobalDilation to multiply by a

given factor the frequency of the EventTick calls. Say I call SetGlobalDilation(0.01), ticks
will happen a hundred times slower.

The package also contains 2 subfolders:

Abilities / Bonuses
This folder only contains a not-yet-implemented blueprint class called
BaseBonus. You may remember how all rank3 abilities modified some
parameters about rank 1 and 2 abilities to give each weapon a different
feeling and set a new gameplay for each one. This will be achieved via
bonuses that will be applied on the weapon. Unfortunately, since I had to
stop before even having a chance to script rank3 abilities, bonuses are Figure 42:
not implemented. TopDownBP/Blueprints/
Abilities/Bonuses

Generated

Figure 43: TopDownBP/Blueprints/Abilities/Generated

This folder contains all the generated actors via abilities. We see charged shot’s projectile, the
ball which replaces the player (with a ParticleFX) when combustion is active, a couple of swipes,
the landmark for the ability with the same name, space anomal and Sphere damager, which is
an invisible sphere that deals damage on collision, used in Magic Blast for example.
It also contains Enemy_Vector struct, a struct with two atributes: a reference to an enemy and
a vector, used by Shove-swipe to calculate and perform properly the pushback mechanic.
Despite seeming a bunch of “simple damage-on-collision” objects, some of them, like the
landmark and shove-swipe have actually about the same amount of code as some “big” classes.

Figure 44: Shove-swipe implementation

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CHARACTER:
The character folder only contains a couple of objects.
 PlayerStatus is an enumeration that contains this values:
[DEFAULT, COMBAT, DEAD]. It is used in Main_Character
to control the state of the player. Resource management
and AI behavior depend on the PlayerStatus.
 Main_Character is the blueprint class that controls Figure 45:
everything about the playable character. It is divided in TopDownBP/blueprints/character
several blocks:
o Initialization: Initializes the Character’s UI (contains the inventory, the resource
bars, the forge GUI etc.) and the character itself. At the time I had to stop, I was
working on the save-game functionality, and there are some nodes here that
were intended to be used in this feature.
o Input Management: Maps the input callbacks to their proper actions
(movement and ability-casting)
o Resource Management: This is the largest part in the class, and is responsible
of:
 Managing the incoming
damage sources
(lowering hp and
eventually dying)
 Regenerating health over
time and managing the
incoming healing abilities
(none at the moment)
 Changing the resource
when we change the
equipped weapon.
 Manage every resource,
both in combat and
outside.
o GUI interaction: Toggling on/off
the inventory and the forge and
dropping items.
o Equipment Management:
Modifying the pertinent values
each time a weapon is equipped
or unequipped.
o Other: Some animation triggers,
testing events and specific
methods needed for some
abilities. Figure 46: Main Character blueprint overview

Despite what it may seem, Main_Character is not a huge blueprint. It is not small, as it has to
trigger lots of things and be aware of many changes, but since it delegates lots of work to other
classes (like Weapon, AbilityBase and CharacterHUD) it is easy to understand.

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DATA:

Figure 47: TopDownBP/Blueprints/Data

This package contains lots of objects, but they are mostly datatables, enums and structs. We will
group and explain them by categories:
As we explained in a previous section, datatables are created from structs, so at least there will
be one struct per datatable.
 Abilities: AbilityStruct contains all the fields of an ability, while Abilities is the datatable
that contains the information of all the implemented abilities. Fig 48 shows some
example rows.

Figure 48: Abilities datatable rows

 ActorTypes: ActorTypeStruct is used by the descriptor to show the player what kind of
element is he hovering, it has a name (for exampe, firendly NPC) and a color to be
displayed. ActorType enum defines which elemtn types we have in the game (for
example, an element can be an enemy, a Master weapon, an ability a Retainer…), it is
used as a datatable index for ActorTypes, as shown in Fig 49.

Figure 49: ActorTypes datatable rows

 Combinations: CombinationStruct is not used. It was used until I decided to improve

the method used to define a
combination, but it gave errors on its
removal so it was left here. Instead,
CombinationStructFinal defines a
combination as an array of integers
containing the IDs of the components
Figure 50: Combinations datatable rows
and a single integer containing the ID of
the resulting weapon. Combinations is the datatable that stores all the possible
combinations, as we can see in Fig 50.

 Descriptions: DescriptionStruct contains all the fields a description uses and

Descriptions is the datatable that defines all the definitions in the game. (~150 entries)

Figure 51: Descriptions datatable rows

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 Items: ItemEnum was used

along with
CombinationStruct, and, like
that, is no longer needed.
ItemStruct contains all the
information about an item. It
will be covered later, but a
weapon is an item and a
weapon at the same time, so
ItemStruct also defines part a
part of weapons. Items is the
largest datatable and
contains the information
about all the items. Since its
rows are too long to be read
here, Fig 52 shows the fields
of an arbitrary item.

Figure 52: Item definition exemple

 Resources: ResourceType is an enum that states all the kinds of resource the character
can have [NONE, FURY, CLARITY, MANA, CHAOS] and is a field in Resource (struct).
Resource defines the fields of a resource, and Resources contains all the resource
information as shown in Fig 53.

Figure 53: Resources datatable rows (all of them)

 Weapons: WeaponEnum, like ItemEnum, was used with CombinationStruct, and is no

longer used. WeaponStruct defines all the fields of a weapon and Weapons is the
consequent datatable containing all the information about all the weapons (remember
that the information of weapons regarding its “item” part is contained in Items, not in
Weapons. Fig 54 displays some rows in Weapons datatable.

Figure 54: Weapons datatable rows

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As you may have noticed, we skipped several structs that do not translate directly into
datatables. These are InventoryStruct and ItemInfoStruct, which are used by CharacterHUD to
manage the inventory, LootStruct, which defines loot by stating which item will drop and how
many (random in a range) and SavedStateStruct, which was supposed to be the struct containing
all the information about a save-point to and is meant to be used to implement the saving
feature.

Together with all these data-objects, there is a Function Library Blueprint:

DataManager is a library used to manage all data in the game, and everything that is related to
information contained in databases should be asked to DataManager ONLY. It contains the
following functions:
 GetItemInfo returns an ItemStruct and a Description of an item given its ID.
 CheckCombination is a complex function that, given an array of components returns an
integer, being this -1 if the components passed don’t result in a valid combination or,
otherwise, the result weapon ID. It is one of the algorithms I’m proudest of.
 GetDescription gets an element description given its ID.
 GetResource returns a Resource (struct) given its proper ResourceType (enum).
 GetWeaponInfo returns a WeaponStruct given its ID.
 CreateInvisibleItemFromID is a method needed to create the combination weapons.
Since to create a weapon we must spawn it in the world, this method spawns an invisible
collision-less copy of the weapon. This way the new weapon will be in our inventory,
and we’ll not see its physical copy (just like any other weapon in our inventory).

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ELEMENTS:

Figure 55: TopDownBP/Blueprints/Elements

Elements package contains 4 blueprints defining “items” in the game. They are the following:
 BaseItem is the parent class for all items (both Collectable Items and Weapons). It is a
pretty big script, so, as we did with MainCharacter, we will cover it by functionalities:
o React to EventTick. There are items that are auto-pickable. That means if you
hold ‘alt’ while you approach them, they will come automatically to you. Each
frame, BaseItem moves the item (if it corresponds) and it relocates the
ItemName and the DistanceAlert HUDs to position them right over the item.
o When it is initialized, it gets references of the GameMode (to access to
descriptions) and MainCharacter and initializes ItemName and the
DistanceAlert HUD’s. It also enables input to capture clicks on the item.
o It manages all the pickup process, checking whether the character is close
enough to enable him to pick up the item, throwing alerts if the item is clicked
but the character is not close enough. Calling the inventory methods to register
the pickup once it is picked up etc.
Generally speaking, it manages the “pickup” component of all the items.

 CollactableItem should be called CollectableItem. It inherits from BaseItem and

represents all the non-weapon items. It contains no logic, but it is important for
inventory purposes that non-weapon items have their own class
 Weapon inherits from BaseItem and represents all weapons. Arrived here we should
explain how weapons work and how do they inherit their abilities.
Each weapon has a specific ability. Rank 1 weapons will have a Rank 1 specific ability,
Rank 2 will have a Rank 2 specific ability (for example, a master axe will always have Full
Strike as its r1 ability and Meteoric Jump as its r2 ability, but its specific ability is Meteoric
Jump). Each weapon will have its specific ability, along with others (of lower rank) that
will inherit from their forging components. When we forge a rank 2 tome, we combine 2
rank 1 tomes. As they both have the same r1 ability, the resulting r2 tome will have that
ability. In rank 4 weapons we will get to choose between one of the 3 r3 abilities we are
combining. Hybrid r3 weapons will have 3 specific (they are not yet implemented).
That explained, we now know what this class is responsible of: Managing which abilities
the weapon have and update them if needed.
It also serves as a bridge between the character and the abilities itself. To cast a spell
the characters calls the weapon’s method CastAbility(int n), then, depending on n, the
weapon will attempt to cast ability 1, 2, 3 or 4.
 HealthRecover is the resource recovering element that spawns after killing mobs. It
recovers your health and mana (providing that is the resource used). It starts chasing
the character at increasing speed when the character gets close enough.

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HUD

Figure 56: TopDownBP/Blueprints/HUD

HUD package contains only Widget Blueprints. Most of them are simple GUI elements, but there
are some others that are really huge blueprints. Let’s analyze them:
 AlertText is a simple text used by BaseItem to alert the player if he’s not close enough
to an item to pick it up or if the inventory is already full. It contains methods to relocate
it in the screen, to set text and to scale it.
 As we mentioned earlier, CharacterHUD is one of the biggest if not the biggest blueprint
in the project. It handles all the logic behind the inventory, the forge system and the
ability info display. As we do with every large blueprint, let’s divide it by functionalities:
o It’s responsible of refreshing the inventory every time an item is picked up,
dropped, forged etc. as well as the equipped weapon.
o Manage inventory slots and equipped weapon slot onClick events
o Manage hovering over slots.
o Handling the equip weapon and store weapon events.
o Sending inventory alert messages (“that item can’t be dropped” for example)
o Manage hovering over the abilities in the character’s ability bar
o Manage the “use item” functionality to open the forge if it’s available
o Refresh the forge UI, checking if the combination is valid and displaying the
result.
o Manage hovering over forge slots
o Calling the proper methods to proceed with a forge
o Calculate the inherited abilities when weapons are forged
o Show the specific weapon ability when hovering it in the forge result slot.
 DeathHUD is the UI shown when the characters dies. It currently contains only a
“restart” button because the save-game functionality is not implemented. Once it is, it
will probably have several more options.
 DialogBox is the UI used to display NPC or MainCharacter dialogs. They are currently
not implemented (and were part of the work-in-progress stuff that had to be left).
 EnemyHealthBar controls the small health bar that appears over enemies. It has
methods to be relocated and scaled. It also handles mouse hovering and sets the owner
unit as selected (just the same as hovering the character mesh).
 InventorySlot defines what elements must a slot have (all slots: inventory, forge and
equipped weapon) and shoots onClick and onMouseOver events that are bound to
functional events in CharacterHUD.
 ItemText is similar to EnemyHealthBar and AlertText. It controls the display of the item
name above the item itself when it is hovered. Has methods to be relocated and scaled.
 PauseScreen handles the Pause menu. It can resume the game, access to options menu,
save the game (not implemented) and quit the game.
It also implements the logics of the options menu, which are:
o Set the relative angle between the camera, the character and base-floor level at
50º, 60º or 70º.
o Zoom in and zoom out (change distance between camera and character).
 SystemHUD was seen briefly earlier in the GameMode blueprint. It contains the
descriptor and the methods to show or hide it.

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IA

Figure 57: TopDownBP/Blueprints/IA

IA (which should be called AI) package contains the blueprint classes of NPCs. They
follow this hierarchy:

Figure 58: IA classes relationship

 EnemyStatus is an enumeration that contains the four possible status of an enemy:

IDLING, CHASING, ATTACKING or DYING.
 NPC is the parent class of all AI entities. It only handles the character hovering, so it
controls only a couple of things:
o Initialize the health bar widget.
o When you mouse-over the NPC change its material to its selection material,
show its description, add the decal (colored ground circle) to the viewport,
change the health bar border color and set MainCharacter’s attribute “target”
to reference this NPC.
 EnemyBase is the parent class for all enemy AI characters (currently only one). It is
responsible of:
o Deciding what action to do depending in the state (EnemyStatus)
o Detecting the player character from a range
o Manage damage intake
o Manage damage output
o Manage its own death and loot spawn
 Melee_bear does not contain additional logic, it is only an information blueprint
containing the specific enemy mesh, with its materials and animations, its specific
damage values etc.
 EnemySpawner performs as an enemy NPC’s squad. Thanks to it, enemies act as a group
(if an enemy of a squad detects the player, all enemies in that squad will begin attacking,
combat will only end and therefore the PlayerStatus variable will be set to DEFAULT
when all enemies in all squads are defeated…). ALL Enemy types Level Amout
ENEMIES MUST SPAWN FROM AN ENEMYSPAWNER Bear, witch 2 5
or they won’t work properly. You can create multiple Figure 59: EnemySpawner example
enemy squads. If can set a squad as shown in Fig 59.
That could create a group with 1 bear and 4 witches, or 3 bears and two witches for
example. This way, instead of spawning various enemies you spawn an EnemySpawner,
passing the parameters through the spawner (constructor).

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 FriendlyNPC has the methods to move to specific positions and to react to clicks. Its
OnClick event doesn’t have any logic tied to it, and instead it calls an event dispatcher
which expects to be treated in another blueprint. An example of that would be the
tutorial. In certain occasions, you want the NPC to move when you click him, in others
you want him to speak/change dialog. This way, you have all the options implemented
and you can choose whatever you want it to do each time you click it. It also has a
method to change its speed (you may want him to run sometimes and walk some
others).
 TutorialNPC inherits FriendlyNPC and it only adds a little bit of logic. This NPC will
constantly look at the character except if he’s walking. When he stops he will turn to
stare at the main character again.

4.b – Level design

And with that said we have finished the package Blueprints. We now head towards the Package
Maps and we’ll see it only contains a single level: TopDownExampleMap.

Figure 60: Editor overview

The reason of this name is quite simple. It was a template map and it was modified from there.
We could write ink rivers about level design, but at a very simplistic level it can be divided in two
sections:
 Level architecture: It’s the part where the designer builts the level, chooses what’s in
the scene, where are the limits (if there are) and it relies mostly in filling the World
Outliner window (it is the upper right window in Fig 60). Architecturing a level can be
done by 2 ways (and normally it is not a matter of one or another but the combination
of both):
o Building landscape: Huge extensions of land that can be blended to create
elevations, pits etc. You can assing several materials to create sections (ie: I have
the path section, the rock section, and the grass section) and then “paint” the
scenario with them. In Fig 60. The base of the level is made with landscape and
4 different layers (road, grass, dirt1 and dirt2).
o Building geometry: Adding props to the scene. From floors to walls. Every single
thing you drag from the content browser to the scene becomes geometry. In Fig
60, left side rocks are props, just like the towers, the pathway and the pantheon.

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Once this processes ar completed, you can add foliage to the scene (All plants and grass
in Fig 60 are folliage except the upper right pines, which are props). The advantage of
adding them as foliage instead of props is that you can “paint” the scene with foliage
instead of dragging every single flower to the scene.
At this point you can define your final scene lights because al shadow-emitters are
already in the scene.
After that you set your invisible walls (big outter purple blocks in Fig 60) and your
triggers.
Finally, you add your scene dynamic components, such as NPC’s, pickup items, the
character spawner, soundFX tied to scene objects etc.

 Level scripting: Once the level is built through level architecture, it’s time to make it do
seomething. We access the level blueprint through the blueprint button in the upper
toolbar.
Level blueprints are programmed the same way as any other blueprint, but they make
heavy usage of particular techniques:
o They can access the objects in the scene specifically, so a lot of references will
probably be saved.
o They abuse the use of event dispatchers. In Fig 61, all the marks correspond to
an event being binded to an event dispatcher call. 16 different events are binded
to event dispatcher calls.
Remember they are used to arrange events in the form of “when this happens,
follow up with this event”, for example:
When the character equips a weapon, spawn 2 bears and unbind the event (so
when the character equips a weapon again this doesn’t happen).

Figure 61: Level blueprint example

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5 - IMPLEMENTATION and TESTING

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We explained all the project structure, covering all the classes and the scripts are there to be
seen, so we are not covering specific code here, instead we will talk about how it was
implemented.
With all what we learned through the previous sections we should now be able to start a new
game, but I did not know almost any of the things we’ve talked about by September 14, so I had
to figure out a way to begin the learning process and the project itself.
What we are about to cover is the development process itself, things that would have come
handy if I learned them sooner, how I iterated versions in the project, what problems I faced and
overtook and which one could me.

5.a – Whish I would have known…

This section will be very short and simple. It covers the couple of concepts I which I would have
known before programming.
 Data structures: I initially knew nothing about how UE4 integrated data structures, so I
figured out that the best way to do it was to have a class initializating everything when
the game was launched and then save it in IATGameMode. I had massive functions in
DataManager to initialize objects. DataManager was, by far, the largest blueprint, with
each of its functions being larger than any of the classes.
Then I discovered datatables and DataManager functions became just accesses to
database.
This issue was a huge time sink. Not less than 40 hours were spent in implementing and
refactoring data management.
 I initially didn’t know how to call a class spawner with parameters, and after researching
about it, I ended up with the conclusion that there were no ‘constuctors’ in blueprints.
It wasn’t until later (a month in) that I discovered the “expose on spawn” checkbutton
in variable details and I started working how it should be done.
Seeing it from a perspective, that wasn’t critical, and, at the time, I remembered all the
specific places where I missed that, so it was just a few hours to refactor.

5.b – Task scheduling

There was not a formal planned schedule in this project, mainly because it was a new technology
and I could not predict when would I be able to implements the design, but also because working
alone provides a certain freedom degree that enables you to handle things as they appear and
plan ahead what you are most enthusiast about.
This will only be a list of ordered tasks. All of them are self-explanatory so there should be no
problem at all.
1. Design
a. Main mechanic
b. Main features
c. Game specifics (weapons and abilities)
d. Game Lore
e. Plot
2. Follow some of tutorials
a. 3rd person Game with Blueprints
b. Inventory UI with UMG
c. UE4 blueprints mouse events
d. Watched lots more, but instead of following the whole process and creating a
project, I just watched them and picked what was useful for me.
3. Start the project with a template
4. Implement character controls and camera

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5. Implement a basic AI
6. Add simple HUD elements (player resources bar and enemy health bar)
7. Implement Pickup items (BasePickUp)
8. Manage selection and hovering over elements
9. Implement inventory
10. Implement equipped weapon UI
11. Create data entries for items (version 1)
12. Implement data retrieving functions in DataManager (version 1)
13. Implement descriptions and descriptor
14. Upload assets: thumbnails for all items and weapons
15. Create data entries for weapons (version 1)
16. Implement Forge
17. Implement auto-pickable items and testing methods to test all the items and the Forge
18. Implement EnemySpawner
19. Implement pause screen
20. Implement specific abilities
21. Implement AbilityBase and relate it to weapon
22. Re-implement all data structures (version 2[final])
23. Implement all HUD support for abilities
24. Upload level design assets
25. Build the level architecture
26. Add final models to weapons, items and characters
27. Implement level blueprint
28. Implement Friendly NPC and edit the level to include him and his actions.
29. – CRASH—

5.c – Versions
In this project there are two ways we define a version:
 By one hand, I worked using GitLab code repository, and tried to commit every single
significant addition (whenever a feature was finished or a bug corrected or a significant
amount of assets added etc.)
This way, we could call almost every single commit a version.
Nevertheless, there are a lot of commits tagged as “unsafe commits” that performed as
mere safety copies when I was doing huge refactoring (like the database massive change
or some inventory structure heavy refactor).

 By the other hand, Oriol (my tutor) and me, had to be in contact and he needed to know
how the project was at any given point.
There is a problem though, if I’m programming in windows I can’t deploy for Mac OS
systems, and, unfortunately, I had no portable device to bring to meetings and show
him. That’s why I decided to upload videos reporting the current state of the game.
I made 4 of them, and they are explained in catalan.

Figure 62: First Iron and Time Report cover

The first one was mad a month in, and covers design, inventory and main setup. Can be
found at: https://www.youtube.com/watch?v=l_li1eQxOdw

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Figure 63: Iron and Time Report - FORGE cover

Second one was a few days later and it covers the first iteration of the forge and the
weapon system. Can be found at: https://www.youtube.com/watch?v=DOU4zIrXAdA

Figure 64: Iron and Time Repor - ABILITIES cover

Third one was released a couple of weeks later, and it covered the first implementation
of the 12 first skills (the only ones present in the current version). It can be found at:
https://www.youtube.com/watch?v=XYHbvUel_h8

Figure 65: Iron and Time Report: tutorial map preview

The last one does not have voice coverage, since it was intended to be done once the
level was fully finished (a state closer to the one we had when the crash occurred), but
I realized a month passed without any video upload, so I recorded very quickly an
overview of what I was working on. Who would have guessed that would be the last
prove of how advanced in development was Iron and Time by the beginning of
December... It can be found at:
https://www.youtube.com/watch?v=9pA-7spR_M0

5.d – Bugs
This section intends to cover some of the problems I encountered during the development phase
and could not figure out by myself what was going on.
Fortunately, Unreal Engine has its own portal to post doubts and the community and the staff
are there to help. It’s called UE4 Answerhub and it works very similar to the very well-known
StackOverflow. I posted there several questions, as shown in Fig 66.
I’ll explain all bugs in its order of appearance (so the opposed of the image).

Healthbars disappearing when AI goes offscreen was a bug I had for a long time. Thanks to a
user called ‘jaragoondoo’ I realised that widget blueprint don’t trigger their EventTick when they
are outside of the viewport. So once they dissapeared from the screen they never relocated
again. To solve this, I update the widgets from it’s owner EventTick. This specific bug post can
be found here: https://answers.unrealengine.com/questions/316420/healthbars-disappearing-
when-ai-goes-offscreen.html

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Figure 66: UE4 Answerhub questions

Why doesn’t the camera follow the main character properly in new levels? and New level
camera issues are actually the same bug posted twice. The first one didn’t get responses, so I
posted it again later on. Even though, I only got one response the second time and it didn’t solve
my doubt. Links two both posts here:
https://answers.unrealengine.com/questions/334158/why-does-the-camera-follow-the-main-
character-prop.html
https://answers.unrealengine.com/questions/347569/new-level-camera-issues.html

How to destroy an actor and its shadow was resolved by a user called ‘Jacky’. I had some pillars
in my level casting shadows when they were destroyed. Thanks to him I realized you have to set
the object to movable instead of static, because if it is in the static, the engine only calculates its
interaction with static lights once. URL to this post here:
https://answers.unrealengine.com/questions/346746/how-to-destroy-an-actor-and-its-
shadow.html

The next one is the one that crashed the editor. It’s not a problem but an UE4 bug, and its
severity makes it worth of its own section.

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5.e – THE BUG

I’ve called this section “THE BUG” because it single handedly destroyed my aims and is
responsible of the relesase version state.
I just finished scripting into the level blueprint to integrate the recently added FriendlyNPC
features to the level. It worked like a charm. You clicked the NPC and it walked to a specific
location, clicked again and he destroys the barriers that block you from entering the pantheon
and walks himself in. Then a portal spawns, and when you enter all the weapons spawn as shown
in the video. It was flawless, but still not finished, so I decided (fortunately as we’ll se in a
moment) not to make a commit. It was a long time without commits, but everything seemed
volatile until I reached a state when I wanted to finish before pushing anything to GitLab.
I finished this functionality but was still working with the save-game feature and the FriendlyNPC
dialog feature, so I coded a little bit more before closing the project. Before doing so I
enthusiastically ran it again and completed for the 30th time the tutorial in its current state.
The day after when I attempted to open the project it crashed.
I tried removing some binary and configuration files and spent a load of hours stashing files in
the repository trying to find whatever was making the editor crash. I even removed the level
itself and the project still crashed.

I did not desperate, but I knew something I could not control was happening, so I posted a
question exposing my problem and waited for an answer.

It is the first one in Fig 66, Help, cannot operate with my project. And can be found in this link:
https://answers.unrealengine.com/questions/348219/help-cannot-operate-with-my-
project.html, anyway I’m copying the entire convesation here:

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Figure 67: HELP, cannot operate with my project full post screening

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6 - CONCLUSIONS

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6.a – What it is
Being totally honest here. It is a decent display of what can be achieved with passion and bad
luck. If I have had only the time I was able to spend in the project (September 14 to December
15, being a total of 3 months instead of the expected 4 and a half) I could have made really
better project.

What I’m trying to say is that having to stop midway has a very punishing disadvantage. About
half of my work isn’t visible in the project. And I’m not talking about assets.
Forge was implemented paying strong attention to rank 3 and 4 weapons for example, and they
are not obtainable. Abilities and AI (to give a couple of examples) were structured in a way to
make it easy to expand, so it meant an important effort that never payed of, given that we only
had about a quarter of the abilities, a fifth of the weapons and only one enemy (I expected to
have 10 to 20 different enemies).

And don’t make me talk about design. No story, no plot, no advanced gameplay mechanics.
Nothing of what made the design special is in the game.
When I first posted the bug I expected it to be solved within a week. At the end of the day I
wasn’t working in any very specific risky fields, so I supposed it was a frequent error with a
generic solution. It is maybe due to the fact that disappointment has been increased gradually
rather than all-at-a-time that now I can stay calm and release this version as it is.

I can’t hide my feelings, I was very passionate at this, spending 8+ hours a day (and have a 6
hours/day job) in the project for more than two months and about 4-5 hours a day for another
month (when university duties required to slow down) but now I feel a huge disappointment:
what was supposed to become my first project and my presentation card to enter the
videogame industry ended up awfully.

Leaving the perceptions aside. As a final degree project I feel I have learnt a lot of useful
knowledge that will surely come handy further in my career. Besides, the project itself is not
near its end, but I think it is still very good as a university project (taking into account part of the
project was getting familiar with the environment).

6.b – What should be and isn’t

I want this point and the next one to be very brief. The Idea of the “What should be and isn’t”
section is to illustrate how this project should improve to achieve a release-ready state without
expanding its contents. There are a few things that should be done if the current version was
the one to deliver.
 Add sounds and music (what is a videogame without them anyway?)
 Implement the two functionalities I was working on: Save-game feature and
FriendlyNPC’s dialogs.
 Actually cook the project (transform it into an executable file to make it available to all
those who don’t have UE4 installed)
 Add a launcher menu

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6.c – What may be

Realistically speaking, I was unsure about the actual chances of finishing all the project as it was
designed.
This is “what may be”, the full implementation of the design. I had lots of ideas for fight
mechanics, I was very impatient to reach the number balance phase and truly configure how a
certain gameplay is rewarded instead of just spamming one ability.

What it may be is THE final product. Not A final product but THE final one.
Developer-wise speaking, most of the logic was already made. The only “pure logic” parts
missing are the rest of the abilities and enemy/combat specific mechanics, the rest is level design
and implementation of weapons final models for example.

The thing here is that early December I reached the point when it all began to happen very
quickly, because the core was already built, and the rest was mainly creative work, so, even if it
was a lot, it is a very rewarding work to do and therefore a job in which is easy to spend hours
and don’t get bored, so I felt confident about finishing the game and adding some cinematics
and voice acting before the deadline.

6.d – What will become

I wanted to write this section here to state that I haven’t given up with this project. I will keep
in touch with the developers, and as soon as they reply, I will resume it where I left it and work
hard to eventually come up with THE final product or even a better one.
I plan to publish this on some platform (probably Steam Greenlight) once it is finished, so if
there’s only one thing you can get from this paper, take the game’s name: Iron and Time,
because it definitely doesn’t end here and perhaps you could hear about it in some point in the
future.

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7 – BIBLIOGRAPHY
Due to its creative nature, there is not a huge amount of sources. Although there are some blogs,
Youtube channels and wikis I used during both design and development phases.

Creating a great design

Tzvi Freeman
Article about the philosophy of design documentation as well as tips and guidelines for GDD
(Game design documentation)
http://www.gamasutra.com/view/feature/131632/creating_a_great_design_document.php

3rd person game with blueprints

Unreal Engine
Video tutorial to introduce UE4 blueprints
https://www.youtube.com/playlist?list=PLZlv_N0_O1ga0IoRrpI4xkX4qmCrhGu56

Inventory UI with UMG

Unreal Engine
Video tutorial to introduce to UMG through the development of an inventory
https://www.youtube.com/playlist?list=PLZlv_N0_O1gZalvQWYs8sc7RP_-8eSr3i

Introduction to UE4 Level Creation

Unreal Engine
Video tutorial to introduce to UE4 Level geometry (architecture)

Tesla Dev Youtube channel

TeslaDev
Youtube channel with lots of short tutorials about Unreal Engine 4.
https://www.youtube.com/user/TeslaUE4/feed

UE4 Answerhub
Unreal Engine
Unreal Engine’s portal to enable the community to share doubts and help each other in UE4
development
https://answers.unrealengine.com/index.html

UE4 Documentation
Unreal Engine
Unreal Engine’s official documentation site.
https://docs.unrealengine.com/latest/INT/index.html

The Art of Game Design

Jesse Schell
The so-called bible of game design. A great book about what game design is about and how it
shoud be done

Wikipedia articles
I used Wikipedia to search about Epic Games, Unreal Engine and Game Engines.
https://en.wikipedia.org/wiki/Epic_Games
https://en.wikipedia.org/wiki/Unreal_Engine
https://en.wikipedia.org/wiki/Game_engine

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