Baboon Demon of Set (5e Creature)
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Baboon Demon of Set
Large fiend, chaotic evil
Saving Throws Strength +10, Dex +8, Wis +8
Maddening Gaze. The demon targets one creature within it can see within 30 feet of it. If the creature can see the demon, the target must succeed on a DC 13 Wisdom saving throw against this magic or be driven insane. At the end of the creature's turn, if it did not attack or take damage from a creature other than the demon it takes 33 (6d10) psychic damage. The madness ends if the demon dies.
Multiattack. The demon can use its Maddening Gaze. It then makes three attacks: one with its bite, and two with its claws. If the demon hits one creature with both claw attacks, it deals an additional 13 (2d6 + 6) slashing damage.
Bite. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 17 (2d10 + 6) piercing damage.
Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 15 (2d8 + 6) slashing damage.
Not unlike a gigantic baboon, the demon of Set stands a full nine feet tall, with black fur, a slavering, fanged mouth and yellow eyes that burn with savage insanity. No such ape ever walked the material plane. This particular breed of demon is created by the evil deity Set to be summoned and employed by powerful spellcasters loyal to the deity. The demon is usually summoned with a powerful artifact called the serpent ring of Set.
From the Conan the Barbarian's story The Phoenix on the Sword.