Dungeon Crawl Stone Soup
The state of DCSS is interesting because it's like a software Ship of Theseus. It's been actively hacked (and slashed) upon for so long that it is hard to claim that its the same game, even if the git commit history shows a direct lineage otherwise. Or, at least, the aspects of the game that I once so greatly admired (which I wrote about here [1]) are longer present. Only a superficial similarity remains. A very opinionated group of core developers with a minimalist design philosophy has driven the project for years now, and the game now is not the game I knew.[1] https://rhizzone.net/articles/crawl/