Beat the game once, and these codes will unlock. To make them work, go to the pause menu, hold all of the shoulder buttons (R1, R2, L1, L2), then press the buttons listed below to activate the corresponding cheat:

Invulnerability - SQUARE, CIRCLE, SQUARE, DOWN

Restore Health - SQUARE, SQUARE, CIRCLE, CIRCLE

All Upgrades - DOWN, UP, TRIANGLE, SQUARE

Infinite Missiles - SQUARE, SQUARE, UP, CIRCLE

Always Devastating - TRIANGLE, DOWN, TRIANGLE, UP

Perfect Mode - CIRCLE, UP, TRIANGLE, X (alternate code - CIRCLE, UP, TRIANGLE, DOWN)

Targeting Indicator Mode - UP, CIRCLE, DOWN, SQUARE

1000 experience points for Gandalf - CIRCLE, TRIANGLE, UP, DOWN

1000 experience points for Aragorn - UP, SQUARE, TRIANGLE, X

1000 experience points for Gimli - CIRCLE, CIRCLE, TRIANGLE, X

1000 experience points for Legolas - X, TRIANGLE, UP, X

1000 experience points for Sam - TRIANGLE, X, DOWN, X

1000 experience points for Frodo - UP, TRIANGLE, UP, DOWN

Unlock Four-Hit Combo For Aragorn - UP, SQUARE, TRIANGLE, DOWN

Unlock Level 4 Abilities for Gandalf - TRIANGLE, UP, SQUARE, X