Don King Presents: Prizefighter Cheats

Unlock Mayorga
Go to the cheat codes section found under the EXTRAS:

POTSEMAG: Ricardo Mayorga

Extra Video "Great Moments in Boxing"
Go to the cheat codes section found under the EXTRAS:

1BESTBUYBEST: Unlock "Great Moments in Boxing" Video

Achievements
Complete each achievement to get the allotted gamerscore.

Hook Hero (20): Take it up top and land 1000 Hooks in any game mode.
3ml of G? (20): KO Milton Forrest.
Blind Fury (20): KO Vassily Kablov.
Can't Touch This! (10): KD an opponent without taking a single shot.
Don King Promoted (30): Join Don's Team during your career.
Easy Pickings (20): Defeat Nino Basilio.
First Steps (5): Turn Pro in Career Mode.
Going the Distance (150): Complete Career Mode.
Hot Shots (50): Achieve 50 Signature Punch KO's in single or multiplayer.
Jab Master (20): Take it up top and land 1000 Jabs in any game mode.
Judge Dreadful! (20): KO Dave Saddler.
Lightning KO (20): KO an opponent in the first 60 seconds of round 1 in any game mode.
Long Way Down (42): Beat every fighter in Career Mode.
New Kid On The Block (5): Create a Career Boxer.
One Armed Bandit (20): KO Sven Zurilo.
Party Animal (20): KO Nyack Quartey after a big night out.
Platinum Puncher (100): Complete Career Mode on Champion difficulty.
Ring a Ding Bling (30): Earn your first career million.
Stick and Move (5): Move more than your opponent.
Swinger (35): Do 50,000 thrown shots.
Tournament Champ (30): Win a Ranked Tournament.
Twinkle Toes (20): Rack up a ring mile.
Uppercut Machine (20): Take it up top and land 1000 Uppercuts in any game mode.
Who's Winning Then? (10): Play ten back to back multiplayer games.
World Champion (50): Become the World Champ in Career Mode.
Xbox LIVE Champ (20): Win 35 ranked fights.
Xbox LIVE Contender (10): Win 15 ranked fights.
Xbox LIVE Journeyman (5): Win 5 ranked fights.
Xbox LIVE Legend (40): Win 50 ranked fights.