Hideous Centipede (5e Creature)
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Large beast, unaligned
Hold Breath. The centipede can hold its breath for 15 minutes.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 6 (1d6 + 3) piercing damage, and the target must succeed on a DC 12 Constitution saving throw or take 18 (4d8) poison damage. If the poison damage reduces the target to 0 hit points, the target is stable but poisoned for 1 hour, even after regaining hit points, and is paralysed while poisoned in this way.
Hideous centipedes are large insects that prowl the undergrowth of jungles in search of prey, which they then attack and devour. They are even known to scurry along riverbeds to feed on fish, and when they feel threatened, their first instinct is to flee and hide underwater.