Defeating Sentinels
Choose Wolverine (at a high level) and run behind the Sentinel. Choose the Brutal Slash attack and repeat it until the Sentinel falls.
Easy kills
This trick works best at the start of the game. Have Rogue in your party and level her up quite a bit. Now once you have skill points, use it on Southern Strike/Smash and increase the abilities level as far as possible while you are
playing the game. Use it on your enemies and it should either kill or take out a large amount of HP. Combine with Leadership to deal more damage.
Extra health and energy
When you receive a new course in the Danger Room, do not complete it. Instead, fail as much as possible. Every time you do the course, you will receive health packs, energy packs, armor, etc.
The best way to get a extra utens is to fail the Danger Room courses. If you complete a course, the next time you send in your team they will not receive anything for their trouble. However, the first "final exam" as a freshman is a very
easy one. Just do not destroy the generators. By doing this, your team can run around kicking butt for quite awhile and collect a lot of times. Note: Make sure all your teammates are set to auto-refill their health at 80% (this can be changed in the first field of the detail view for your characters). Also, watch for the inevitable cut off time (about a half hour in). At this point, the villains will no longer give anything up. Then, destroy the reactors and leave. Make sure to sell Forge
anything you absolutely do not need; otherwise about halfway through your available time your inventory will be full and you can miss out on some good items.
Leadership
The Leadership quality possessed by Storm and Cyclops can be a tremendous asset to the team. This skill multiplies both damage and experience when successfully completing a combo. At its highest level Leadership will multiply damage by 150% and experience by 25%. Use Storm and Cyclops together to multiply these values a second time. That’s 625 damage of a base 100 attack. With a good roll of the die, combo attacks upwards of 1500 are possible by the end of the game.
Play As Beast
Successfully complete level 1.
Play As Colossus
Successfully complete the Nuclear Facility level.
Play As Cyclops
Defeat Mystique.
Play As Emma Frost
Locate Emma Frost in X Mansion after the Nuclear Facility level.
Play As Gambit
Successfully complete level 3.
Play As Ice Man
Successfully complete level 1.
Play As Jean Grey
Successfully complete level 1.
Play As Jubilee
Successfully complete level 2.
Play As Nightcrawler
Successfully complete level 2.
Play As Psylocke
Successfully complete the NYC Riot/Muir Island/Sewer level.
Play As Rogue
Successfully complete level 1.
Play As Storm
Successfully complete level 1.
Secret Art
Collect all Sketch Books.
Unlimited combo
Start the combo by pressing X then A(2), X(2), then keep repeating A(2), X(2), A(2), X(2), etc. It is a lot easier if done slowly and you wait for the character to swing.
X-treme Costumes
On the main menu press Up, Up, Right, Left, Down, Down, Start.