Xtreme alternate costumes
When your at the main menu press Up(2x's), Right, Left, Down(2x's), Start. While playing, go to an Xtraction save location and use the button next to "Skin".

Alternate costumes
Finish the game to have the classic costumes (Bobby Drake/original Iceman, 1990's Colossus/without metal, original Beast, 1980's Cyclops, original Jean Grey/Phoenix, original Nightcrawler, street clothes Magma, 1990's Wolverine/Weapon X) available.

Play as Beast
Finish level 1 completely.

Play as Cyclops
Beat Mystique when your in the New York City Riot level.

Play as Gambit
Finish level 3 completely.

Play as Storm
Finish level 1 completely.

Play as Emma Frost
Find Emma Frost in X Mansion after the Nuclear Facility level.

Play as Colossus
Finish the Nuclear Facility level completely.

Play as Magma
Finish Magma's second training round.

Play as Nightcrawler
Finish level 2 completely.

Play as Professor X
Go into the Astral Plane for the first time.

Play as Ice Man
Finish level 1 completely.

Play as Jean Grey
Finish level 1 completely.

Play as Jubilee
Finish level 2 completely.

Stat increase
Collect the hidden Comic Books to raise your characters' stats.

Bonus Danger Room tasks
Collect the hidden Danger Room Discs to have more tasks in the Danger Room available.

Play as Psylocke
Finish the New York City Riot level completely.

Play as Rogue
Finish level 1 completely.

Artwork
Collect all 19 Sketchbooks to have the artwork in Colossus' room available.

Hints & Tips

Extra health and energy
When you do receive a new course in the Danger Room, do not finish it. Instead, fail as much as you can. Every time you do the course, you will get health packs, energy packs, armor, etc.

A good way to get a extra utens is to fail the Danger Room courses. If you finish a course, the next time you send in your team they will not get anything for their efforts. However, the first "final exam" as a freshman is an easy one. Just do not demolish the generators. By doing this, your team can run around kicking butt for a long time and collect plenty of times. Note: Make sure all your teammates are set to auto-refill their health at 80%. Also, watch for the inevitable cut off time roughly a half hour in. At this point, the villains will no longer give you anything. Then, destroy the reactors and exit. Make sure to sell Forge anything you do not need or roughly halfway through your available time your inventory will be full and you can miss out on a few good items.

Easier experience
Make sure you locate the "Focus 601" Danger Room disc. Then once you have passed the exams (Qualifying 100, 200, 300, 400, and 500) and can access the "Legends" menu, select "Focus 601". In this mission, you have to beat five Master Acolytes, which will give you more than 297,000 experience points each. Then each time that you do this mission, you are assured to get at least 1,100,000 experience points.

Make your way to qualifying exam 400 and keep failing it. Do not worry about Professor X; just keep killing Astral Fury to receive roughly 117,000 experience each time. Colossus can kill them in just one hit.

Enter the Danger Room and choose Challenge: Legends. Now take Cyclops, Storm, Jean, and anyone you want to level up. When you do beat the first three Bosses, switch to Jean and go to the center area between the first two doors. Then use Psychic Shout to score a lot of experience. However, do not complete the challenge. Let time run out and try again. You can get to level 40 and above quickly by doing this. Note: Storm's Chain Lightning or Lightning Legend will also work well.

To preform this trick, you first need to have Storm and Cyclops learn the Leadership ability. This will work best if the skill is at the maximum. Once this is done, always have Cyclops and Storm in your party with two other members that you wish to level up. Start fighting your enemies, except this time use your abilities more. This ability will work once you perform a combo with either Storm or Cyclops' abilities. It should give you more damage and experience points. To make this more valuable, try your best to execute a combo with both Storm and Cyclops' abilities. This should double the normal amount of bonus experience and damage. The Leadership ability's maximum capabilities is at 150% damage bonus, and 25% experience bonus; and if you did managedto combo both Storm and Cyclops' abilities this should give you a 250% damage bonus and 50% extra experience. This trick should be used in the Danger Room Focus 601 or Qualifying Exam 400. These are the areas that give the most experience points with the most time for you to preform your attacks.

Easier kills
This trick will work best at the start of the game. Now have Rogue in your party and level her up a bit. Now once you do have skill points, use it on Southern Strike/Smash and raise the abilities level as far as you can while you are playing the game. Use it on your enemies and it should either kill or take out a hefty amount of HP. Combine with Leadership to deal even more damage.

Beating Marrow
Use this trick to beat Marrow after GRSO soldiers have attacked the tunnels. At first is seems very hard, but it is best to have someone like Storm on your team who can fight at long range. After you kill Marrow and all of her henchmen, two Marrows will appear. One will have a green shield and will appear under one of the torches. Right away do Cyclone Fury with Storm or another Xtreme long range power. This will kill her. You will still have to kill the other Marrow. Then, attempt to find the special Marrow after each kill of the regenerating Marrow. After you have killed the special Marrow three or four times, just beat the other Marrow.

Beating Mastermold
To beat Mastermold, first use Wolverine and slash away at his feet and jump when he steps. When the three Sentinel Controllers come out, batlle with them and dodge Mastermold's missles by running in circles around the generators. When he has his shield, turn on the three generators and wait until it goes away. From now on, use a long range fighter to kill him. Just remember to avoid the missiles.

Beating Sentinels
First choose Wolverine when he is at a high level and run behind the Sentinel. Then choose the Brutal Slash attack (R2 + X) and redo it until the Sentinel falls.

Just have Colossus get Bands Of The Gladiator and Legend Smash. Just two hits will drop them.

Unlimited combo
First start the combo by pressing Circle then X(2x's), Circle(2x's), then keep redoing X(2x's), Circle(2x's), X(2x's), Circle(2x's), etc. It is easier if done slowly and you do wait for the character to swing.

Throw Wolverine
Simply have Wolverine and Beast in your party. Then choose Beast and face Wolverine. Press Throw and Beast will pick up Wolverine and throw him at an enemy, doing a good deal of harm. Note: Rogue can also throw Wolverine like Beast can.

This is the signature move of Wolverine and Colossus combined (but can also be done with Beast). Just play as either Colossus or Beast and press Square to throw Wolverine.