Croc

Here is level select: at Press Start screen press X+Y+Z until Enter Password screen comes up. Then w/Joypad enter LLLLDRRLLDRDLUR.

On level 3-5, Leap of Faith, jump on the first platform with arrows on it, and when it drops, you will land on another platform below you. It will teleport you to another part of the level. You will find four smash boxes. Smash them to get four extra lives. Repeat this process until you have all the lives you need.