FusionDex

Shelledge is unable to retract its long tongue, therefore it must frequently dip it into a special shell to prevent it from drying out. It fiercely guards this shell, and will wrap its sticky tongue around anyone who gets too close.

Apparently this Pokemon is born when a departed spirit inhabits a sword. At night, it burrows a hole in the seafloor with its broad tongue to make a place to sleep.