At the main menu, select the "Extras" option. Then, select the "Cheats" option, and enter one of the following codes to activate the corresponding cheat function:

Invincibility in Story mode

Enter Down, Down, Right, Up, Left as a code.
Infinite Chi

Enter Down, Right, Left, Up, Down as a code.
4x damage multiplier

Enter Up, Down, Up, Right, Left as a code.
Big heads in Story mode

Enter Down, Up, Left, Right, Right as a code.
All multiplayer characters

Enter Left, Down, Left, Right, Down as a code to unlock all multiplayer characters.
Dragon Warrior costume in Multiplayer mode

Enter Left, Down, Right, Left, Up as a code to unlock the Dragon Warrior costume in Multiplayer mode.

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