Secret New Battle Stages In Battle Mode:

At the title screen press START rapidly until 
you hear a sound and then go to battle and you
will see new stages. 

Submitted by theman_10030@yahoo.com


Secret Battle Stages:

Looking for more variety in your multiplayer
battles? Go to the game selection screen 
(where you choose between adventure mode, 
battle mode, etc.). If you have a controller 
with a pause button press it, or just press the
start button quickly and repeatedly until you
hear a chime. You need to tap it quickly, as if
you were playing a track-and-field game. Now go
into battle mode and the four extra battle levels
(In the Gutter, Sea Sick, Blizzard Battle, Lost
at Sea) will be enabled. We have tested this code
with BOTH the US and Japanese version and we 
assure you it works. 

by unknown