Rocky

Double punch damage:
Hold R1 and press Right, Down, Left, Up, Left, L1 at the main menu.

Double speed boxing:
Hold R1 and press Down, Left, Down, Up, Right, L1 at the main menu.

All default boxers and arenas:
Hold R1 and press Right, Down, Up, Left, Up, L1 at the main menu. Note: This does not unlock Mickey or the Rocky Statue.

All default boxers, arenas, and Rocky Statue:
Hold R1 and press Right(3), Left, Right, L1 at the main menu.

All default boxers, arenas, Rocky Statue, and Mickey:
Hold R1 and press Up, Down(2), Left(2), L1 at the main menu.

Full stats in tournament and exhibition modes:
Hold R1 and press Left, Up(2), Down, Right, L1 at the main menu.

Full stats in movie mode:
Hold R1 and press Right, Down(2), Up, Left, L1 at the main menu.

Win fight in movie mode:
Hold R1 and press Right(2), Left(2), Up, L1 at the main menu. Press L2 + R2 during a fight in movie mode to automatically win.

Alternate costumes:
Press Circle while selecting a boxer at the character selection screen.
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Silver class knockout tournament:
Win the bronze class knockout tournament.

Gold class knockout tournament:
Win the silver class knockout tournament.

Fight as Apollo Creed 1:
Defeat him during Story mode.

Fight as Apolo Creed 2:
Defeat him during Story mode.

Fight as Big Chuck Smith:
Defeat him in Story mode.

Fight as Big Yank Bill:
Defeat him in Story mode.

Fight as Billy Snow:
Defeat him in Story mode.

Fight as Bob Cray:
Defeat him in Story mode.

Fight as Buddy Shaw:
Defeat him in Story mode.

Fight as Burt Judge:
Defeat him in Story mode.

Fight as Clubber Lang:
Defeat him during Story mode.

Fight as Dipper Brown:
Defeat him in Story mode.

Fight as Ernie Roman:
Defeat him in Story mode.

Fight as Ivan Drago:
Defeat him during Story mode.

Fight as Jack Reid:
Defeat him during Story mode.

Fight as Joe Chan:
Defeat him in Story mode.

Fight as Joe Czak:
Defeat him in Story mode.

Fight as Kofi Langton:
Defeat him in Story mode.

Fight as Mac Lee Green:
Defeat him in Story mode.

Fight as Mickey Goldmill:
Successfully complete movie mode under the Champ difficulty setting.

Fight as Randy Tate:
Defeat him during Story mode.

Fight as Rocky 2:
Defeat Apollo Creed 1.

Fight as Rocky 3:
Defeat Apollo Creed 2.

Fight as Rocky 4:
Defeat Clubber Lang.

Fight as Rocky 5:
Defeat Ivan Drago.

Fight as Spider Rico:
Defeat him during Story mode.

Fight as Tim Simms:
Defeat him in Story mode.

Fight as Tommy Gunn:
Defeat him during Story mode.

Fight as Union Cane:
Defeat him in Story mode.

Fight as Vito Soto:
Defeat him in Story mode.

Rocky Statue:
Successfully complete Movie mode under the Contender difficulty setting.

Hint: Easy knock downs:
In movie or any other mode, when the fighter approaches you at the start of the fight, hit him with your special power punch. When he comes to you again, hit him with another special power punch, then attack him with body shots. This will drop his strength and let you knock him down repeatedly, thus winning the fight.