Max up your heros in the Gambit Stage of this tough game. In Spider-Man/X-Men you snag an
extra life each time you grab 100 Stars. The easiest way to build up Stars in the Gambit Stage is to proceed through the stage until you reach the fourth Green Globe and leap over it, right off the screen.
Try to land in the same spot that you jumped from, without touching the Globe. If you manage to land in the correct spot, you'll get a ton of Stars. Quickly repeat this procedure over and over, and you should be able to build up about ten lives before you're nailed by the giant wheel. If you repeat the entire procedure again and again, you can build up 99 lives.