Stonefin (5e Creature)
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Large elemental, neutral
Damage Immunities poison
Earth Glide. The stonefin can burrow through nonmagical, unworked earth and stone. While doing so, the stonefin doesn't disturb the material it moves through.
Multiattack. The stonefin makes two attacks: one with its bite and one with its slam.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) piercing damage.
Slam. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) bludgeoning damage.
Stonefins are shark-like elementals made up of earth and water that can freely swim through solid earth and water alike, often attacking from ambush. A stonefin's body is mostly made of mud with many scattered flecks of stone, including a large stone on its back reminiscent of a shark's fin. When stonefins attack, the only warning that their targets get is usually a stone sticking out of the ground and rapidly moving closer.
Elemental Nature. A stonefin doesn't require air, food, drink, or sleep.