One Piece - Pirates Carnival cheats and cheat codes for Gamecube

Unlock Skypiea 1 stage:
First get the Grand Line 3 board, then, choose the "Board Game" option.
Select the "Password" option and enter the following password:
X, A, A, Y, B, A, B, X, X 
Input from left to right, and when you reach the third column, 
go to the second row to continue. Note: Make sure that the Playstation 2 
system time and date match the actual date and time. 

Unlock bonus games, larger boards, cards:
Play the board game the complete it, to unlock all the games that you've 
played in versus mode. You can access to larger boards and all board game 
cards in the gallery. 

Unlock voice collection
Go to the Member's Game and the Captain's Game and play each of the mini-games
to unlock the voice collection to unlock an option on the Voice Collection menu.
Note: You don't have to win the game, just play.