The Crabbot (タニッシー Tanisshī) appears in Bubble Man's stage and in the third section of Dr. Wily's castle. One shot knocks the shell off, making it move faster. One shot is enough to defeat it in the normal difficult on the NES version of Mega Man 2. A weapon that can be aimed low helps to finish it easier.
Crabbot's Japanese name is a play of Tanishi (タニシ), term for freshwater snails from the Viviparidae family.