Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
F.E.A.R. - F.
Unreal Tournament - Unreal is a series of first-person shooter video games developed by Epic Games.
Doom - Doom is a science fiction horror-themed first-person shooter video game in which players assume the...
Quake - Quake is a series of first-person shooter video games released by id Software.
Turok - Turok is an Action-Adventure, FPS, Survival, Single and Multiplayer video game developed by Propaganda Games published by Disney Interactive Studios.