First Person Shooter (FPS):

Picks

Free - open source FPS game based on Quake III arena style.

A colourful FPS game set in a real 3D environment.

Fun deadmatch-style fps game with ability to edit map-geometry.

Semi-realistic shooter game in old western-styled atmosphere.

A free and fast-paced first person shooter that combines addictive, arena-style gameplay with rapid movement and a wide array of weapons.

Stealth operations and fast action game play against terrorism.

Free singleplayer FPS game built on an entirely new and unconventional engine.

Battle inside the castle of Wolfenstein.