Activate the following cheats by entering the corresponding sequences of buttons at 'Main Menu' > 'Extras' > 'Cheats'.

CHEAT FUNCTION - CHEAT CODE
4x Damage Multiplier - UP, DOWN, UP, RIGHT, LEFT.
All Costumes - RIGHT, LEFT, DOWN, UP, RIGHT.
All Moves - DOWN, DOWN, LEFT, RIGHT, LEFT.
All Multiplayer Characters - LEFT, DOWN, LEFT, RIGHT, DOWN.
Big Head Mode (story mode) - DOWN, UP, LEFT, RIGHT, RIGHT.
Dragon Warrior Costume (multiplayer mode) - LEFT, DOWN, RIGHT, LEFT, UP.
Full Upgrades - DOWN, DOWN, UP, LEFT, RIGHT.
Infinite Chi - DOWN, RIGHT, LEFT, UP, DOWN.
Invincibility(story mode) - DOWN, DOWN, RIGHT, UP, LEFT.