GI Joe: The Rise of Cobra Cheats for Wii
These bonus costumes become available at the start of the game by entering the corresonding code using the D-pad at the 'Main' menu. If you have entered the code correctly you will hear a 'Yo Joe!' sound effect as confirmation.
Unlock Classic Duke:
Press Left, Up, -, Up, Right, +
Unlock Classic Scarlett
Press Right, Up, Down, Down, +