Press [Shift] + C to activate the chat
function during game play in single player mode. Enter one of
the following codes. then press [Esc] to end chat and activate
the corresponding cheat function.

Code
Kill target DieDieDie
Mission completed IamTheMaster
Unlimited fuel GoingAndGoing
Unlimited ammo ShootEmUp
Invincibility BigAssShields
Invisibility WonderWoman