Warface - Warface - is a free online shooter with diverse PVP modes, exciting PVE missions, outstanding arsenal and millions of fans around the world!
Xonotic - Xonotic is a free (GPL), fast-paced first-person shooter that works on Windows, OS X and Linux.
Insurgency - Take to the streets for intense close quarters combat, where a team's survival depends upon securing crucial strongholds and destroying enemy supply in this multiplayer and cooperative Source Engine based experience.
Counter-Strike - Counter-Strike is a PC-exclusive FPS video game developed by Valve Corporation.
Sudden Attack - Sudden Attack is an Action, Role-playing, Science-fiction, Co-op, FPS (First-person Shooting), and Multiplayer video game created and published by Nexon GT.
Quake - Quake is a series of first-person shooter video games released by id Software.