Daywalker Difficulty
To unlock Daywalker difficulty, go to the main menu, then press and hold L1. Then press: LEFT, CIRCLE, UP, DOWN, SQUARE, CIRLCE, X.

Get Infinite Ammo
To get infinite ammo, go to the main menu and hold L1. Then press: LEFT, CIRCLE, RIGHT, SQUARE, UP, TRIANGLE, DOWN, X.

Get Infinite Health
To get infinite health, go to the main menu, then press and hold L1 while you press: TRIANGLE, SQUARE, TRIANGLE, SQUARE, TRIANGLE, CIRCLE, TRIANGLE, CIRCLE.

Get Infinite Rage
To have infinite rage, either visit the DMV, or go to the main menu of this game and hold L1. Then press: LEFT, DOWN, LEFT, DOWN, RIGHT, UP, RIGHT, UP.

Invincibility For NPCs (Non-Player Characters)
To make the players you're taking care of (on escort levels) invincible, go to the main menu and hold L1, then press: DOWN, UP, LEFT, LEFT, CIRCLE, RIGHT, DOWN, SQUARE.

Unlock All Missions
To unlock all missions, go to the main menu. Press and hold L1, while you press these buttons: DOWN, UP, LEFT, LEFT, CIRCLE, RIGHT, DOWN, SQUARE.

Unlock All Weapons
To unlock all weapons, go to the main menu. Press and hold L1, then press: SQUARE, CIRCLE, DOWN, LEFT, CIRCLE, CIRCLE, TRIANGLE.