GameBoy Advance Cheats: Ready 2 Rumble Boxing: Round 2 Cheats

Box as Michael Jackson
At the main menu, highlight the "Arcade" option, then press Left(2), Right(2), Left, Right, L + R to unlock Michael Jackson.

Box as Shaquille O'Neal
At the main menu, highlight the "Survival" option, then press Left(4), Right(2), Left(2), Right, L + R to unlock Shaquille O'Neal.

Box as Rumble Man
At the main menu, highlight the "Championship" option, then press Left(2), Right, Left, Right(2), Left, Right, Left, L + R to unlock Rumble Man.