Duke Nukem 3D and Shadow Warrior have both been available before as ports from the source code. They’ve been updated by Devolver Digital to support higher resolutions and other enhancements and more importantly now officially support Linux for the first time!
They’re classic first person shooters that are completely ridiculous and fun. As somebody who grew up playing both games, I am not sure how people who didn’t would take their sense of humor.
Both games also include their expansion packs. Shadow Warrior has Wanton Destruction and Twin Dragon. Duke Nukem is the Atomic Edition including a new chapter with Duke Caribbean: Life’s a Beach, Duke it Out in D.C, and Duke: Nuclear Winter.