Omastar

Omastar uses its tentacles to capture its prey. It is believed to have become extinct because its shell grew too large and heavy, causing its movements to become too slow and ponderous.

Before its own heavy shell led to its extinction, Omastar swam the seas in search of prey. Even the hard shells of prehistoric Shellder stood no match to Omastar's deadly powerful bite, and were quickly made a meal of by having their insides sucked out.