Cheat Artifacts and Keys

Press START hold R + L and input CROSS, CROSS, CIRCLE, SQUARE, TRIANGLE, CROSS. A new option will now appear on the pause menu. (Unvferified)

Cheat: Invincibility and All Weapons

Pause the game. Hold R and enter DOWN, UP, SQUARE, TRIANGLE, TRIANGLE, CIRCLE, DOWN, UP, SQUARE AND TRIANGLE. An extra category will unlock on the senu screen. Select it, and you can turn "Invulnerability" and "Gain All Weapons" on and off.