X-Men: The Official Game Cheats
Comic alternate costume
Collect all Sentinal Techs with a character to unlock his or her alternate comic costume.
Danger Room missions
Progress through the game to unlock the first three Danger Room missions. Six more Danger Room missions are unlocked by collecting all Sentinel files and Weapon X files with all characters.
Bonus Iceman Danger Room level
Press Right(2), Left(2), Down, Up, Down, Up, Start at the Cerebro Files menu.
Bonus Nightcrawler Danger Room level
Press Up(2), Down(2), Left, Right, Left, Right, Start at the Cerebro Files menu.
Street alternate costume
By collecting all Weapon X files with a character you will unlock his or her alternate street costume.
Bonus Wolverine Danger Room level
Press Down(2), Up(2), Right, Left, Right Left, Start at the Cerebro Files menu.