Extra Ammo:
For extra ammunition, pause the game and hold L1 + L2 for 10 seconds. With these buttons held, press Triangle, Left, Left, Left, Circle, Triangle, Down. From here on you can refill your ammo by pausing the game and selecting the Ammo option that appears.

Healing:
To heal yourself, pause the game and hold L1 + L2 for 10 seconds. With these buttons held, press Down, Right, Left, Triangle, Right, Down. From here on you can heal yourself by pausing the game and selecting the Health option that appears.

Level Skip:
Slip past the warden with this trick. Pause the game and hold L1 + L2 for 10 seconds. With these buttons held, press Left, Triangle, X, Right, Circle, Triangle, Down.

Play as Fwank:
To play as Fwank, highlight Mamma and press L1, Circle, R1, Down, Down, R1, Circle, L1, L1. A red balloon will appear over Sister Magpie. Move the cursor to her slot and Fwank will be playable.

Play as a Bloody Mess:
Enter the health code, then kill yourself. When you're laying on the ground in a pile of blood and gore, pause the game and refill your health. You'll resume play as a bloody mess.

Weapon Power-up:
To enhance the carnage, pause the game and hold L1 + L2 for 10 seconds. With these buttons held, press Left, Up, X, Circle. From here on you can power up by pausing the game and selecting the Power option that appears.