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Snailicorns are large snail-like creatures that have the characteristics of a unicorn, such as a large horn, hence the name, which is a portmanteau of snail and unicorn. They appear only in New Super Mario Bros. and are never seen outside of ice stages. They can be very dangerous, as a mere jump is not enough to defeat them, and fireballs are ineffective. However, as jumping on them sends them back a few feet, this tactic can be used to send them off of a cliff nearby, though they'll reappear if Mario leaves the area and comes back. Also, a full-speed Shell Mario or a stray shell will knock them out.