Game Cube Cheats: Mario Superstar Baseball Cheats

Secret Characters
Not all players are unlocked from the start so you'll need to unlock them if you want to enjoy and experince all of the characters.

Baby Luigi - Complete Challenge Mode with Yoshi.
Dixie Kong - Complete challenge mode with Donkey Kong
Toadette - Complete Challenge Mode with Peach
Petey Piranha - Complete Challenge Mode with Wario
Monty Mole - Complete Challenge Mode with Mario

Unlock Koopa Castle Stadium
Complete Challenge Mode once