Various Cheats
Pause gameplay and select Cheats. Select Enter Cheat and enter any of the following "Codes":
SKETCHY = Pen and Ink Mode
SONIC = Fast Running
Invincibility:
Enter GODLY as a cheat code.
All weapons
Enter LOADED as a cheat code.
Unlimited ammunition
Enter SORTED as a cheat code.
Level select
Enter SKIPPY as a cheat code.
Open All Cheats
Just go to the cheats option and enter GOLDENPIE and it will unlock all cheats except the level cheat.