Quake 3: Team Arena

Never before have the forces aligned. United by name and by cause, The Fallen, Pagans, Crusaders, Intruders, and Stroggs must channel their power into an allied operation where teamwork is the only method of mass destruction. Four distinct games test each troop's synthesis and strength to exacting degrees. Cooperation is the only course of action, and war, the only alternative. Soldiers once alone in their struggle, now face the Arena as one.

Source: Steam