While playing a game in single player mode, press [Shift] + C to activate the 
chat function. Enter one of the following codes, then press [Esc] to end chat 
and activate the corresponding cheat function:

Cheat Code - Result
BigAssShields - Invincibility 
WonderWoman - Invisibility 
ShootEmUp - Infinite ammo 
GoingAndGoing - Infinite fuel 
IamTheMaster - Mission completed 
DieDieDie - Kill target