Tritosor

It has a pliable body without any bones. If any part of its body is torn off, it grows right back.

It apparently had a huge shell for protection in ancient times. It lives in shallow tidal pools.

Long ago, its entire back was shielded with a sturdy shell. There are traces of it left in its cells.

When its natural enemy attacks, it oozes purple fluid and escapes.

It has strong regenerative capabilities. Even if parts of it are bitten off by fish Pokémon, it will return to normal within a few hours.

Plankton, invisible to the naked eye, is its main food source. It comes onto the land periodically, but the reason for this is not known.

Long ago, it had a shell on its back. There’s now a vestigial plate on its back that’s hard but thin.

Their shape and color change, depending on their environment and diet. There are many of them at beaches where the waves are calm.

Its search for food sometimes leads it onto land, where it leaves behind a sticky trail of slime as it passes through.

The softness of its body helps disperse the force of impacts, so although its body is uncommonly squishy, it’s also surprisingly resilient.

Eats beach sand for nourishment. Should one Gastrodon encounter another of a different color, a fierce battle will inevitably ensue.