GI Joe: The Rise of Cobra Cheats (PS3)

If you press the Right, Up, Down, Down, Triangle buttons in that sequence this bonus
costume will be added to your playable characters roster and will be an available option
from the begininning of the game.

When you have completed the game and the credits have finished a cutscene will start and
the bonus mission will be unlocked and ready to play.

Complete the bonus mission to unlock Baroness, Destro, and Firefly as playable characters
when you buy them for 15 Battle Points each.