Lethal Lava Land: Touch lava without injury glitch
Make sure the hundredth coin you get is under the bridge. After getting it, a Star appears for getting 100 coins. Get the Star to do the victory dance on the lava without getting burnt. When prompted to continue, answer "Yes" to cause two things will happen. You will either continue and the game will notice you were on lave, inflicting you damage. Or the game will forget and lava will not hurt you until you exit the level.