When you're at the Juggernaut, choose Wolverine as your character. Jump on the platform and wait for Juggernaut to run buy. Run behind him and hit him 4-5 times, then run to the opposite platform. Keep doing this until he dies.
To easily defeat Magneto, use Wolverine. Stand in the corner until Magneto starts to bring up the debris. Walk over to him and use the jumping upper-cut move. This will knock off the debris and hit Magneto. Repeat this until he's defeated.
Extra Life With Psylocke on First Level
When the first door opens and a guy comes quickly press Forward, Forward, Y. Then when he gets up make sure he does NOT move from that spot! While he is still in the spot hold down and then Jump and press the Y button while still holding down. If you did it right you will get a plate that has a X on it. You will have to get three of these to get a extra life. To get the second one walk towards the little cliff just before the second door. When you get to the cliff just before you walk off jump then press the Y button. To get the last one you will have to beat the robot boss and when the ground shakes and falls there will be these things you'll have to jump over on the last one the X-plate will be right by it. When you get all of them, you'll hear a funky sound.
Start the apocalypse ahead of schedule with these passwords.