Nicktoons Unite! (PlayStation 2)
CheatingDome.com
Bonus Charecter Skins
Beat level 1 and start a new game.
Get All New Power-ups And All New Levels
Go to extras and then type in "levelpower" to actavate this cheat.
Unlock All Levels
Hold L2, X, Right, Left, Down, Triangle and hold down R1 for 10 seconds.