While playing a game, press X to display the team menu. Next, hold Select, press Left Analog-stick Up and rotate it clockwise three times, then immediately rotate it anti-clockwise three times, while continuing to hold Select. Note: Your selected character will run around when this is done. While in the same menu, you should notice that a new icon has appeared under the log icon in the lower right hand corner of the screen. Highlight it and press X to display the cheat menu. The cheat menu allows all weapons, unlimited health, unlimited weapon energy, warp to the last level, and level selection.
Unlock All Levels Normally
Unlock all levels normally by finishing the game once. The game's master save will acknowledge that milestone and allow you to select the stage to start on from the Title Screen (does not apply to Continue/Load Games).
Unlock Cheats
During gameplay, press X to bring up the team screen. Then press and hold SELECT. Push the left analog stick UP, then rotate it three times to the right (clockwise), then immediately three times to the left (counter-clockwise). If you do the code correctly, you will see another icon appear under the Log icon. Selecting it will take you to the Cheat Menu, which includes:
Max Energy
Turn Invulnerability On
Turn Team Invulnerability On
Turn Team Invulnerability Off
Turn Infinite Weapon Energy On
All Weapons
Access All Levels
Skip Level