Black River Demon (5e Creature)
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Black River Demon
Large fiend, chaotic evil
Saving Throws Dex +7, Int +5, Wis +5
Demon Fire. A creature that touches the demon or hits it with a melee attack while within 5 feet of it takes 11 (2d10) cold damage.
Mimicry. The demon can mimic humanoid voices. A creature that hears the sounds can tell they are imitations with a successful DC 14 Wisdom (Insight) check.
Multiattack. The demon makes two talon attacks.
Talon. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 24 (4d8 + 5) slashing damage plus 5 (1d10) fire damage.
A long time ago, all creatures spoke the same tongue and worshipped a single deity. Over time, man and beasts developed different tongues and then this deity was forgotten by almost everyone. The human shaman who still make sacrifices to it do so secretly, and the the beasts that still call it their master withdrew to a parallel realm. One of these beasts is called the black river demon, though that is not its true name. Those who know its true name can summon the demon and send it out to hunt and kill. Outside its realm, the black river demon has an unsteady form and appears to be part man-like creature and part reptile. Its surrounded by green and blue flames that burns cold and doesn't shed light, and has long sharp talons.
From "Beyond the Black River", Robert E. Howard, 1935