This is a cartoon-like first-person shooter which combines fast gameplay with vibrant colours. It uses the Quake3 engine, which is well supported by current hardware.
A team based first person shooter (FPS). Tremulous is free to download and play.
In Tremulous there are two teams: Aliens and Humans. Aliens can have such awesome feats as wall-walking (dizzying to say the least), pouncing from great distances, and spraying poisonous gases. Humans can obtain advanced weaponry and armor, and plant strategic devices such as turrets to defend their base.
Tremulous features a unique upgrade system, where players from each team must make a certain number of kills to gain new upgrades (aliens can evolve into more powerful aliens, and humans can obtain better items and gear).