Mario Tennis

Enter these codes at the Ring Tournament selection under the Special games option:

N24K8QN2P - Bowser Cup
V2UFMPUZM - IGN64 Cup
M1C2YQM1W - Luigi Cup
A3W5KQA3C - Mario Cup
UOUFMPUOM - Wario Cup
OF9XFQOFR - Peach Cup
LA98JRLAR - Waluigi Cup
MM55MQMMJ - Donkey Kong Cup
ARM6JQARU - Blockbuster Cup
J6M9PQJ6U - Nintendo Power Cup
48HWOR482 - MarioTennis.com Cup

Bowser's brother:
Play with wario a normal game and hold the ball 40 min in the field. If you did it correctly then you can play with the brother of bowser.