While playing, press ENTER on the number pad to display the developer window.

Complete next objective ... cisco
All inventory ... refill
Chicken grenades ... chickenrun
Faster movement ... run
God mode ... superman
Invisibility ... shadow
Paintball mode ... extremepaintball
Squirrel launcher ... squirrelkite
Suicide ... god
Unlimited ammunition ... ammo
Unlock Hero characters ... unlockheros
Hunt down enemies ... gogetem