Xtreme Costumes
On the Main Menu enter UP, UP, RIGHT, LEFT, DOWN, DOWN, START.

Cyclops
Beat Mystique.

Ice Man, Jean Grey, Beast, Rogue, and Storm
Finish First Level.

Jubilee and Nightcrawler
Finish Second Level.

Gambit
Finish Third Level.

Colossus
Beat Nuclear Facility level.

Emma Frost
Beat Nuclar Facility level (meet in X-mansion).

Magma (on field missions)
Beat Blob in Magma/Cyclops mission.

Psylocke
Beat NYC Riot, Morlock Rescue, and Muir Isle fight levels.

Wolverine 90's, Weapon X
Beat the game.

Original Cyclops, Cyclops 80's
Beat the game.

Original Jean Grey, Phoenix
Beat the game.

Original Beast
Beat the game.

Colussus without metal, Colussus 90's
Beat the game.

Bobby Drake, Original Iceman
Beat the game.

Street Clothes Magma
Beat the game.

Original Nightcrawler
Beat the game.

Storm's white outfit
Beat the game.