Eurypterid (5e Creature)
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Large beast, unaligned
Amphibious. The eurypterid can breathe air and water.
Multiattack. The eurypterid makes three attacks: two with its claws and one with its sting.
Claw. Melee Weapon Attack: +5 to hit, reach 5 ft. , one target. Hit: 11 (2d8 + 2) bludgeoning damage, and the target is grappled (escape DC 13). The eurypterid has two claws, each of which can grapple only one target.
Sting. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 8 (1d12 + 2) piercing damage, and the target must succeed on a DC 13 Constitution saving throw or be poisoned for 1 minute. Until this poison ends, the target is paralyzed. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
An ancient creature of enormous size; these creatures are solitary hunters who prey on smaller, less adept swimmers. Their enormous oar-like arms can propel them at immense speed through water, making them great ambush predators. Eurypterids rarely come on land during the colder seasons, emerging only if food is scarce in the reefs below. During summer, massive hoards of these creatures pour out of the waters to lay eggs on the beach. Few who come to witness this event live to tell the tale, as eurypterids become incredibly hostile when laying eggs. These creatures are found only in very specific regions of the world, where temperatures in the ocean stay at a relatively constant 30 degrees Celsius.