When you are facing Wa Wa, crunch will shoot things at you. He will fire blue beams that you should jump over. When he fires green things, duck. Hop from one panel to another. When you reach Crunch quickly spin. Watch out -- the panels will sink. Try to get a head start on each run. Once Crunch jumps back at the beginning, run. When you spin him the next two times, do not stop running.