An asian style dungeon tileset made by me (Phitt). You are free to use this tileset in any Grimrock or Grimrock 2 mod as long as you give credits (and, obviously, don't try to sell the mod).

The tileset has all the basics you need to create a full-blown dungeon, it could use some more variation though. I may update it from time to time.
All the dungeon assets start with 'ctomb', there is also a small wall tileset that can be used in exteriors and interiors starting with 'pagoda'.

There is a dungeon editor file with a small dungeon included. The dungeon is only for testing purposes and to give examples on how to use the tileset. It has no real gameplay worth mentioning.