Medusa Snake (5e Creature)
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Medium monstrosity, unaligned
Skills Perception +3, Stealth +7
Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 7 (1d6 + 4) piercing damage, and the target must make a DC 13 Constitution saving throw, taking 10 (3d6) poison damage on a failed save, or half as much damage on a successful one. If the saving throw fails by 5 or more, the creature is instantly petrified. Otherwise, a creature that fails the save begins to turn to stone and is restrained. The restrained creature must repeat the saving throw at the end of its next turn, becoming petrified on a failure or ending the effect on a success. The petrification lasts until the creature is freed by the greater restoration spell or other magic.
Covered in scales that resemble bits of stone, medusa snakes are infamous for their poison that — like a medusa's gaze — can turn flesh to stone in moments. The snakes themselves cannot be affected by this aspect of their poison, nor by similar causes of petrification. Some medusas keep these snakes as pets and guardians, for they need not worry that their gaze might petrify the beast, while others are kept by dao and other intelligent creatures of elemental earth.