While playing the game, hold L + R and press Y(3), X.
Extra lifeWhile playing the game, hold L + R and press A(3), Y, X, Y.
Full healthWhile playing the game, hold L + R and press A(3), Y.
All gadgetsWhile playing the game, hold L + R and press Y(2), X, B, A, Y(2), A.
Bueno Nacho costumeHave the Game Boy Advance game Kim Possible: Revenge Of Monkey Fist in the cartridge slot to unlock the Bueno Nacho costume.
Commando costumeHave the Game Boy Advance game Kim Possible 2: Drakken's Demise in the cartridge slot to unlock the Commando costume.
Super Suit costumeHave the Game Boy Advance game Kim Possible 3: Team Possible in the cartridge slot to unlock the Super Suit costume.