The Orthocera Shell is a Hardmode sentry that drops from Orthoceras. It summons a stationary flying Orthocera sentry that shoots streams of acid at nearby enemies. The acid streams pierce up to two enemies along with inflicting the Venom debuff.
Its best modifier is Ruthless. The Mythical modifier provides the widest array of stat bonuses, but these primarily affect the initial summon rather than the resulting minion. Additionally, minions cannot deal critical hits. The only lasting advantage a Mythical Orthocera Shell has over a Ruthless one is knockback.