Assault Cube is a first person shooter based on the Cube engine. It has a single player mode and multiplayer. This FPS is realistic and team oriented. The graphics are nice and the weapons are decent. It is a fast paced game but very enjoyable. There are two teams. One is the Cubers Liberations Army (CLA) and the other is the Rabid Viper Special Forces (RVSF). This game is free and works well on Linux.