I've long considered Slagovich to be an ideal campaign home base.
PCs can begin their adventuring careers in the frontier city of Akesoli in the Lands and Environs of the D&D Wilderness (I've always liked the area north of there for B7 "Rahasia") and join a caravan across the Sind all the way to Slagovich (the caravan encounters, including the buried temple, from X4 "Master of the Desert Nomads" could be used).
Illustration from X6 "Quagmire!" depicting the port of Slagovich (note mountain range in the background)
Arriving in Slagovich, there are 12 adventure hooks to be had:
1. If the characters take their time wandering through the streets of Slagovich, they come across the following advertisement:
Wanted: Wild horses, mules, and camels. Best prices paid. 100 gp for camels, 75 gp for horses, 50 gp for mules. Bring roped animals to the agent of Bondee Slagomann at the corrals on the outskirts of town"
Module X6 "Quagmire!"
Bondee is a wealthy Slagovich merchant. His daughter, Kazandra Slagomann, is later captured by the mermen of the Sunken City, and must be rescued.
Alternatively, Bondee could hire the characters to find out what happened to his daughter. This might lead into a more natural hook for module X6 "Quagmire!".
The PCs learn that lizard men have been harassing the trading ships in the area around East Fang Cape, and that no one can recall the last time a ship arrived from Quagmire.
2. Module I1 "Dwellers of the Forbidden City" on the Serpent Peninsula:
For several months, possibly even years, there have been reports of banditry in the jungles to the south. Merchants carrying precious loads of rare goods from the jungle lands have been waylaid, their goods taken and their men captured or killed. Even then, those who survived these raids had to face headhunters, brain fever, giant leeches, cannibals, and leopards. Few men ever returned. The stories they told were fantastic and addled, surely brought about by disease and the horrors with which they had to deal. Singing snakes, twisted and deformed ape-men, men who were not men, and writhing, horrid flowers filled their tales-surely such things were not to be believed. Nonetheless, something had destroyed the caravans.Furthermore, none of the goods taken from the caravans has ever appeared in the markets of the north, at least as far as the merchants can tell. Some were certainly identifiable - rare pieces of art, scrolls, books, and other items destined to fetch good prices in the kingdoms of the north. It could only mean that someone or something was hoarding a great treasure in the jungle. Prompted by this information, adventurers set out to find the bandits and gain their treasure. Your party is one of these.
Module I1 "Dwellers of the Forbidden City"
Map of Serpent Peninsula from X6 Quagmire! (left) and Champions of Mystara (right) indicating the location of Onyo Maata, a suitable location for I1 Dwellers of the Forbidden City
Four additional reasons for seeking the Forbidden City are given:
3. Revenge
A group of merchants has hired your party to stop the raiding (as explained in the module Background) permanently. Characters must find and enter the city, determine who is responsible for the raids and destroy that person or group. The characters must also ensure that no further raids occur. This could be done by destroying all of the inhabitants, bribery, creating feuds, sealing all the ways in and out of the city, or any other plan the players might invent. The merchants would no doubt like to have the goods they lost to the raids returned, so the DM might wish to create a very well-guarded storehouse of these items.
Module I1 "Dwellers of the Forbidden City"
4. Rescue
Many important people have been disappearing from the courts of nearby lands. The people are being kidnaped by the Black Brotherhood (a secret group the DM must create) and given to the yuan ti for safekeeping. The Brotherhood wants to help the yuan ti by weakening the power of the surrounding kingdoms. First the characters must discover who is doing the kidnapping, and then trace the kidnappers to the yuan ti. A group of the Black Brotherhood would be based in the city. The prisoners would be hard to find, for they are scattered throughout the city. Some might be easy to rescue, while others might be very difficult to rescue.
Module I1 "Dwellers of the Forbidden City"
5. Conquest
A local potentate (or other ruler) has declared that his ancestors were once the masters of the Forbidden City (although there is no proof to his claim). He wants the adventurers to enter the city, scout it, and, if possible, clear it of all foul monsters.
Module I1 "Dwellers of the Forbidden City"
6. Defense
A courier carrying important information was recently attacked and robbed while crossing the jungle. Found before he died, the courier told his rescuers of the theft. Since his papers reveal the weaknesses and strengths of a nearby kingdom, the monarch of that land has offered a reward for the return of the documents. At the same time, the rulers of several other lands have likewise offered rewards if the documents should just happen to reach their hands first. However, once the characters reach the city, they will learn that an evil army is being assembled to attack all the surrounding lands. To save themselves and others from slavery, the adventurers must try to prevent this attack from occurring. The players must defeat or join other parties also after the stolen documents. How they do it is left to the players and the DM.
Module I1 "Dwellers of the Forbidden City"
Map of Hule from module X5 "The Temple of Death" with recommended location for the city of Highport from A1 "Slave Pits of the Undercity" (left) and the Gulf of Hule (right) from "Adapting classic AD&D modules to a Mystara campaign" in Threshold: the Mystara Magazine #22
7. Modules A1-4 "Against the Slavers" in the nearby Gulf of Hule:
It is time to put a stop to the marauders! For years the coastal towns have been burned and looted by the forces of evil. You and your fellow adventurers have been recruited to root out and destroy the source of these raids. But beware, hundreds of good men and women have been taken by the slavers and have never been seen or heard from again!
Module A1 "Slave Pits of the Undercity"
The four adventure hooks from module X9 "The Savage Coast":
8. Gold Rush
There's gold...lot's of it...west of here. It's supposed to be all along the coast of someplace called Orcs Head Peninsula. An old seer told me it was there. It's ours for the taking if we can get past the natives who live there. He said the peninsula is a dangerous place, but if we're smart, we'd never want for anything again.
Module X9 "The Savage Coast"
9. Cartographers Guild
The Cartographers Guild of Slagovich has offered us a handsome reward for a more detailed map of the coastline areas of Orcs Head Peninsula. If we agree to sail along the coast of the peninsula to map the lands of the area, they will give us 50,000 gp each, and they've already given us a map that shows the areas where hidden treasures might be found, and a map of a legendary lost city. No adventurer has been able to find the treasures or the city yet.
Module X9 "The Savage Coast"
10. Rival Brotherhoods
The local clerics of the Brotherhood of Light are looking for a few good adventurers to discover the whereabouts and the activities of their rivals, the Lawful Brotherhood. They believe the Lawful Brotherhood is engaged in some exploitive pursuits, and are becoming too powerful. They have noticed ships in the harbor that fly the Lawful Brotherhood flag, but they have not been able to determine the Brotherhood's business here. The ships come and go only at night—a good indication that something is not right.
Module X9 "The Savage Coast"
11. Merchant Company
The Pure Gold Merchant Company is searching for a party of adventurers with a ship. Rumors of gold along Orcs Head Peninsula have caused a panic among the owners of the company. Their ships are all on other expeditions—they have no time to wait for their return. If there is gold to the west, they want it first, and are willing to pay for it.
Module X9 "The Savage Coast"
Site of the lost city of Risilvar in the Forbidden Highlands of Orc's Head Peninsula, from module X9 "The Savage Coast", a fitting location for the Hidden Shrine of Tamoachan (left). Illustration by Jeff Dee (right).
12. Finally, there could be rumours regarding module C1 "The Hidden Shrine of Tamoachan"
Notes:
Originally posted on Dragonsfoot (September 8, 2018)
See also "The Voyage of the Princess Ark (Part 17): The Slagovich affair" by Bruce Heard, in Dragon #171 (July, 1991)