FASA 365 Day 225, Magnum Monstrum Locusta, (Large Monster Lobster) 150-250 ft.
Three Pronged Claws. Opposable “thumb”, Center Driller, Outer Crusher. Dominant (larger) claw on the left.
The bladder underneath its torso fills with air to assist it maneuver underwater. Otherwise it would collapse under the weight of its thick dense shell.
Horned like a Rhinocerous. Attacks from beneath and after its prey sinks… bottom feeder.

Artists Note: You’d need a bunch of Navy SeaBees just to crack the shell, let alone build the pot to boil it.