With any character, when you are in need of desperate help and you need to put damage on a large group of enemies or a boss, press the A button, and your character will perform one of his/her specials. If you press a direction, then A for your special, your character will perform a different special which may be more or less effective. Don't use these too often because it takes away 5-7% of your health each time you use it. You have to have at least 65% health to perform these.
Hidden Bonus Extra Life
At the very beginning of level one, before you do anything, move all the way to the bottom left of the screen and press B, or the pick up button, depending on what your control settings are set to. You will get an extra life or 1-up.
Hidden Bonus Life
This bonus life is only on level 1. At the very start of the game on level one, go to the bottom of the screen and move all the way back. Press punch/grap and you will have picked up an extra life (1-up).
Very Effective Moves
This set of buttons during gameplay on an enemy are very effective. Press right right B. If you use this with Max, he will slide on his back forward and trip the enemy. If you use Axel, he will do a crawling motion forward and come up with a very strong punch. If you use the skater kid, he will do a flip move into a kick on the enemy. If you use the girl, she will do a backflip into a sliding kick. Using this move on the characters are very effective, and they aren't hard to figure out.