Shell Mario

Shell Mario is a form of Mario that Mario can become in New Super Mario Bros. by touching a Blue Shell. It allows him to use the Tanooki Suit-like ability to dodge the attacks of enemies when he crouches, tucking into it. However, if he ducks while running he will hide in the shell and the shell will slide through the world, bashing through lots of enemies. This maneuver is called a Shell Dash.