During the game, press Talk, enter one of the following codes, then press Enter:
Invincibility: god
Invisibility: notarget
All weapons: guns
All weapons and infinite ammo: tears
Extra ammo: ammo
Full health: health
Full armor: armor
Weapons, full ammo, armor, health: kfa
Increase health and reflexes: gear
Level skip: maphole
Position mode: pos
Ghost mode: poltergeist
Display build version: build