FusionDex

Bellster have small mouths that cannot fit most aquatic Pokémon, so they gather fish bones using their vines and digest those instead. The only time their shell slams shut is when there is danger nearby.

It swims in the sea by swallowing water, then jetting it out toward the rear. A Bellster's thin and flexible body lets it bend and sway to avoid any attack, however strong it may be.