Mirra

Mirra is a rare, parasitic enemy appearing in the Kirby series that is exclusive only to the Mirror World. It is a nervy blob-like enemy that is able to stretch its expandable body over an surface- in this case a Mirror Door. Mirra is very shy, and certainly doesn't want to get hurt. So whenever it spots Kirby marching forward, it, along with the Mirror Door it's latched onto, burrow into the ground until it feels safe. The only way Kirby can get Mirra to exit and reenter the room the Mirra is in. The only way it can be defeated is with a projectile or a long-ranged ability. If Kirby lands just a single hit on it, it will be instantly destroyed and will leave behind the Mirror Door it was guarding.