You start this level in water. Unfortunetly for you, this is a boss fight. Anyway, a giant bone snake-like thing comes in to play. Don't try to hit him until a health meter appears. Its head comes in. It will point it's head at you until you stay still for a short time. He will start to chomp his teeth rapidly, and when he does, dodge him. Try to grab the end of his tail. When you do, he turns blackish-gray and stays still. Drag him to the spikes around here and slam him on those spikes. Repeat the process until he is dead. As every boss does, he drops a gold medal.