Unlock Characters
Colossus:
Beat Nuclear Facility Mission.

Cyclops:
Defeat Mystique in NY.

Emma Frost:
After Nuclear Plant Mission.

Gambit:
Complete Third Level.

Ice Man, Jean Grey, Beast, Rogue, and Storm:
Beat the First Mission.

Jubilee, Nightcrawler:
Complete Second Mission.

Magma: Complete her second round of training.
Psylocke: Beat the New York riot Mission.