Crabion

The Crabion is a crab-like creature protected at its front side but not its rear.

=In fanon games=

In Pikmin: The Return of the Puffmin
The Crabion is a crab-like enemy in Pikmin: The Return of the Puffmin that has a protective shell covering its front. Because its backside is unprotected, attack it from behind, although its tendency to flee often makes this difficult.