Bronze class 
Select "Championship Mode" from the main menu. Then, choose 
"New Game" and enter "RUMBLE POWER" as a gym name to unlock all 
class bronze boxers in championship mode. Note: This also unlocks 
Kemo Claw in arcade mode.

Silver class 
Select "Championship Mode" from the main menu. Then, choose 
"New Game" and enter "RUMBLE BUMBLE" as a gym name to unlock 
all class silver boxers in championship mode. Note: This also 
unlocks Bruce Blade in arcade mode.

Gold class 
Select "Championship Mode" from the main menu. Then, choose 
"New Game" and enter "MOSMA!" as a gym name to unlock all class 
gold boxers in championship mode. Note: This also unlocks Nat 
Daddy in arcade mode.

Champ class 
Select "Championship Mode" from the main menu. Then, choose 
"New Game" and enter "POD 5!" as a gym name to unlock all class 
champ boxers in championship mode. Note: This also unlocks Damien 
Black in arcade mode.

Taunts 
During a match, hold X + A or Y + B to taunt your opponent.

Restore energy 
Knock your opponent down, then sweep the Analog-stick in a 
Full-Circle or repeatedly press L + R while they are stunned to 
restore some of your boxer's energy.

Fight in two-tier arena 
Enter "Arcade Mode" from the main menu and select two player mode. 
Then at the character selection screen, hold L while selecting a boxer.

Fight in championship arena 
Enter "Arcade Mode" from the main menu and select two player mode. 
Then at the character selection screen, hold R while selecting a boxer.

Fight in gym ring 
Enter "Arcade Mode" from the main menu and select two player mode. 
Then at the character selection screen, hold L + R while selecting a 
boxer.

Fight in outdoor ring 
Enter "Arcade Mode" from the main menu and select two player mode. 
Then at the character selection screen, hold X + L + R while selecting 
a boxer.

Hidden images 
Place the game disc in a PC compatible CD-ROM drive to find twenty 
hidden images in the "Extra" directory.