Get default boxers, arenas & Rocky statue & Mickey:
Go to the main menu and HOLD R and press Right, Down, Left, Up, Left, L.

Get 2X Speed Boxing:
Go to the main menu and HOLD R and press Down, Left, Down, Up, Right, L.

Get default boxers, arenas & Rocky statue:
Go to the main menu and HOLD R and press Right, Right, Right, Left, Right, L

Get All Default Boxers & Arenas:
Go to the main menu and HOLD R and press Right, Down, Up, Left, Up, L.

Get 2X Punch Damage:
Go to the main menu and HOLD R and press Right, Down, Left, Up, Left, L.

Get Max Stats for Movie Mode:
Go to the main menu and HOLD R and press Right, Down, Down, Up, Left, L.

Get Max Stats for Tourney & Exhibition Modes:
Go to the main menu and HOLD R and press Left, Up, Up, Down, Right, L.

Win Fight in Movie Mode:
Go to the main menu and HOLD R and press Right, Right, Left, Left, Up, L. During the fight press Black + White to win fight.

Get Silver Class Tournament:
Win the Knockout Tournament on Bronze

Get Gold Class Tournament:
Win the Knockout Tournament on Silver

Get Mickey Goldmill:
Win the Movie Mode on Champ setting

Get Rocky Statue:
Win the Movie Mode on Contender Setting