They are, quite literally, Sea Scorpions; so unless you have an aquatic mount with some hefty torpor resistance, stay away from the sea floor. They can't swim, but hover right above the ground, kinda like a trilobite (They spawn in Viking Bay on Ragnarok, and can easily follow you onto land from there). If you really feel like it, they do drop Black Pearls when harvested, and so can be valuable as long as you keep an eye on your depth/what else may lurk in the darkness.

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