Deep Prelate (Etrian Odyssey III) Edit
Deep Prelates are found on B14F, and will chase the party if gates are opened. They can use various elemental attacks to strike the whole party. If joined by a Deep Coistrel, they can perform a deadly attack called Sea Guillotine, which damages and may cause instant death to all party members.
Deep Prelates may also be summoned by Otherspawn.