Caves of Qud completely entranced me when I first played it. It's a great example of what modern Roguelikes can be. My only complaint is that the story and some writing is just bad (in a cringe kind of way). But most of the worldbuilding is excellent and really captures a sort of Dune-inspired science-fantasy feel. I think the game would be basically flawless (in my opinion) if they removed or reworked the Barathrumites and the Consortium of Phyta.