So lately I've been into Duke Nukem 3D and Blood, and I'm thinking this addiction might last for awhile, so I'm wondering what else to look for.
Here's all the ones I know of:
Blood (only the first one, Blood 2 used LithTech engine)
Duke Nukem 3D
Ken's Labyrinth (I think this is like, a very early iteration of the Build Engine)
Shadow Warrior
Are there others? Did I miss some?