X-Men: The Official Game Cheats

Bonus costumes
Collect all Weapon X files with a character to unlock their street costume. Collect all Sentinal Techs with a character to unlock their comic costume.

Danger Room missions
Successfully complete an Act with a character to unlock one of their Danger Room mission. Successfully complete all three Acts with a character to unlock all three of their bonus Danger Room missions.

Iceman Danger Room missions
At the Cerebro Files menu, press Right(2), Left(2), Down, Up, Down, Up, Start to unlock the bonus Iceman Danger Room missions.

Nightcrawler Danger Room missions
At the Cerebro Files menu, press Up(2), Down(2), Left, Right, Left, Right, Start to unlock the bonus Nightcrawler Danger Room missions.

Wolverine Danger Room missions
At the Cerebro Files menu, press Down(2), Up(2), Right, Left, Right, Left, Start to unlock the bonus Wolverine Danger Room missions.

Achievements
Complete each achievement to get the allotted gamerscore:

Champion Iceman (70) - Collect all Sentinel Tech as Iceman.
Champion Nightcrawler (70) - Collect all Sentinel Tech as Nightcrawler.
Champion Wolverine (110) - Collect all Sentinel Tech as Wolverine.
Danger Room Iceman (20) - Complete Act 1 of the game.
Danger Room Nightcrawler (20) - Complete Act 2 of the game.
Danger Room Wolverine (30) - Complete Act 3 of the game.
Evolution Iceman (125) - Iceman has been upgraded with all available mutations.
Evolution Nightcrawler (125) - Nightcrawler has been upgraded with all available mutations.
Evolution Wolverine (120) - Wolverine has been upgraded with all available mutations.
Secret Identity Iceman (70) - Collect all Weapon X Files as Iceman.
Secret Identity Nightcrawler (80) - Collect all Weapon X Files as Nightcrawler.
Secret Identity Wolverine (110) - Collect all Weapon X Files as Wolverine.
X-Men (50) - Accumulate 950 achievement score.
Xavier Institute Iceman (0) - Complete Iceman's training mission.
Xavier Institute Nightcrawler (0) - Complete Nightcrawler's training mission.
Xavier Institute Wolverine (0) - Complete Wolverine's training mission.