Press ~ or § during game play, then activate the following cheats by entering the corresponding codes. Note: Codes must be re-activated after each new level.

CHEAT FUNCTION - CHEAT CODE
Enable all cheats - AllCheats
All keys - AllKeys
Upgrade laser - UpgradeLaser
Upgrade ammo - UpgradePlasma
Unlimited ammo - UnlimitedAmmo
All weapons - GimmeAll
Full health - FullHealth
Toggle God mode for NPCs - NPCGodmode
Toggle god mode - Godmode
Toggle gpeed hack - SpeedHack
Toggle fog - Fog
Debug mode - DebugCollGeom
Floating camera - FreeCamera
Hide the object you shoot - ShootHides
Toggle user interface - NoGUI<0 or 1>
Change the light - PostProcess
Toggle stencilshadows - Stencil
Wireframe graphics - Wireframe
Unknown - NoDoFNear
Unknown - RenderFilter
Unknown - Stats
Unknown - JWT
Unknown - TimeScale
Unknown - AiDebugAgent
Unknown - DebugCam
Unknown - LoadLevel
Unknown - TimeDemo
Unknown - EnableDoF
Unknown - DebugShader
Unknown - ColorBalance
Unknown - NormalMaps
Unknown - Bloom
Unknown - RenderFlares
Unknown - AimTime
Unknown - AimFoVFactor
Unknown - LogLevel
Unknown - FlushLog
Unknown - CollGeomOnly
Unknown - CollGeomWireframe
Unknown - CollGeomShow