Pause the game, choose the "Options" selection, highlight the "Select mission" option, then hold Left + R1 + L1 + Select + Square + X (simultaneously). For the PAL version of the game, hold L1 + L2 + R1 + R2 + Square + Circle + X.
All weapons and infinite ammunition
Pause the game, highlight the "Weapons" option, then hold Right + L2 + R2 + Circle + Square + X (simultaneously). Note: Only the weapons normally available during the current level will become selectable. For the PAL version of the game, hold Select + L1 + L2 + R2 + Circle + X.
Super ammunition for the Silenced 9mm (North American version)
Pause the game, highlight the "Silenced 9mm" under the "Weapons" option, then hold Left + L1 + R2 + Select + Square + X (simultaneously). If you entered the code correctly, Gabe will say "Understood".
Expert mode
At the title screen, hold Left + L1 + R2 + Select + Square + Circle + X (simultaneously). If you entered the code correctly, the phrase "Damn it" will be spoken. For the PAL version of the game, hold L1 + L2 + R2 + Square + Circle + X.
Weak enemies
Pause the game, highlight the "Map" option, then hold Right + L2 + R1 + X (simultaneously). If you entered the code correctly, you will hear a laugh. For the PAL version of the game, hold Right + L1 + R1 + R2 + Circle + X.
