Enter the codes at the Start Game Screen:

Note! The L3 and R3 buttons are when you press Left or Right analog stick. If the code doesnt work, reset your X-Box and try again.

Cheat Mode: 
Up, Left, R, Y, Down, L, B, White, A, Start. 

Invincibility: 
L3, R3, Down, Left, Down, Left, B, Y, Start. 

Unlimited turbo: 
Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start. 

Unlimited ammo: 
Black, White, L, R, R3, R3, Y, X, Start. 

All Boats: 
Up, Down, Left, Right, L, B, X, X, R3, Start. 

All Arenas: 
X, Y, Up, Right, Left, Down, Up, Down, L, L, Start. 

Rubber duck mode: 
R3, L3, R, L, Black, White, Up, Down, Left, Right, Start. 

Blood ball mode: 
X, Y, White, Black, B, A, Left, Up, Right, Down, Start. 

Puffer Fish: 
A, B, Black, White, Y, X, R3, R3, L3, L3. Start. 

All Battle Modes: 
Y, A, X, B, L3, R3, Black, White, R, R, Start. 

Import boat: 
Y, B, X, A, L, R, Left, Right, L3, R3, Start.