Considering the previous two failed attempts at making D&D movies, I was positively surprised at this one. Having followed the Book of Vile Darkness promotion a year past, I knew that the movie was in production for quite some time, along with its source material (the D&D 4th Edition Book of Vile Darkness for those wondering), and there are several references in the movie that will appear more than anything as name dropping or inside jokes - which can be a good thing, provided that you know what is being referred to. To be precise, the Heroic and Paragon tiers are mentioned in regards to magic armor, and the main character also encounters thassil root poison, and both Vicious and Vorpal longswords, along with a Bag of Holding (the last of which is used in a manner that most seasoned D&D players would be proud of). Furthermore, both the sun god Pelor and the Shadowfell, the D&D realm of the dead (along with Gloomwrought, the closest thing it has to a capital city) are mentioned. The inclusion of shadar-kai and a goliath instead of the typical elves and dwarfs is also a nice touch, and in line with this, it breaks with many typical fantasy tropes.
As mentioned above, knowing the source material beforehand can be a boon in the case of this movie, especially since the Book of Vile Darkness in its previous edition was suited only for people aged 18+ because of its... well, "vile" contents, along with a focus on playing evil characters that is unheard of elsewhere in typical D&D, where the player characters are usually the heroes - and the main character in the movie faces some of the same moral quandaries that are mentioned directly in the D&D source material. There is also the fact that the main characters mention a red dragon at some point in the movie that is clearly not a dragon, but a Nhagruul Dragonspawn, and is thus again tied to the Book of Vile Darkness supplement for D&D 4th Edition. It is strange that this isn't mentioned at all in the movie, however.
The acting isn't the best that one could want (maybe except for the Vermin Lord, who fits the bill perfectly) and some of the lines are somewhat illegible at times, but I would praise the story in that it both manages to feel somewhat "realistic" (in-universe at least) while staying interesting and entertaining.
All in all, I would consider this movie a success, in that it was both entertaining and thought- provoking, the latter of which especially with the aforementioned moral quandaries in mind. It's probably not for everyone, but I would recommend it to any somewhat seasoned D&D player, along with anybody interested in a fantasy film a bit darker and grittier than the usual.