Complete the indicated task to unlock the corresponding character.

Abomination: Defeat Abomination.
Bi-Beast: Defeat Bi-Beast.
Classic Hulk (Savage Hulk): Collect five comic book covers.
Green Scar (Planet Hulk): Successfully complete the game.
Grey Hulk: Smash 10,000 objects.
Hulkbuster Iron Man: Have a saved game file from Iron Man.
Ironclad: Defeat the U-Foes, trick a U-Foe into KOing his teammate, and defeat Abomination.
Maestro: Destroy a building in each neighborhood.
Professor Hulk (Smart Hulk): Complete all jump challenges.
Savage Hulk: Collect five comic book covers.