Arma 2: Operation Arrowhead - Arma 2: Operation Arrowhead is a Tactical, First-person Shooter, Single and Multiplayer video game created by Bohemia Interactive Studios and published by 505 Games.
Call of Duty - Call of Duty is a first-person and third-person shooter series by Infinity Ward.
Unreal Tournament - Unreal is a series of first-person shooter video games developed by Epic Games.
S.T.A.L.K.E.R.: Shadow of Chernobyl - S.
Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
Quake Live - Quake Live is a Fantastic, Action-Adventure, FPS (First-person Shooter), Survival, Single and Multiplayer video game developed by Id Software and published by Bethesda Software.