Cerberus, Variant (5e Creature)
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Large fiend (devil), lawful evil
Saving Throws Str +11, Con +9, Wis +7
Cerberus's Curse. Whenever Cerberus hits a creature with its bite attack, that creature is forced to remain in its current plane until the curse is removed by the remove curse spell or other magic.
Keen Hearing and Smell. The Cerberus has an advantage on Wisdom (Perception) checks that rely on hearing or smell.
Multiple Heads. The Cerberus has three heads. While it has more than one head, the Cerberus has advantage on saving throws against being blinded, charmed, deafened, frightened, stunned, and knocked unconscious.
Whenever the Cerberus takes 56 or more damage in a single turn, one of its heads dies. If all its heads die, the Cerberus dies.
Pack Tactics. The Cerberus has an advantage on attack roll against a creature if at least one of its Hell Hound's allies is within 5 feet of the creature and the ally isn't incapacitated.
Relentless Tracker. The Cerberus knows the distance to and direction of any creature under the effect of its curse, as long as the creature and the Cerberus are on the same plane of existence. If the creature being tracked by the Cerberus dies, the Cerberus knows.
Soul Scent. The Cerberus can pinpoint, by scent, the location of any soul within 30 feet of it.
Multiattack. The Cerberus makes as many bite attacks as it has heads.
Bite. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 11 (1d8 + 7) piercing damage plus 10 (3d6) fire damage.
Fire Ray. Range Spell Attack: +11 to hit, range 30/90 ft., one target. Hit: 21 (6d6) fire damage.
Fire Breath (recharge 4-6). The Cerberus exhales fire in a 15-foot cone. Each creature in the area must make a DC 17 Dexterity saving throw, taking 35 (10d6) fire damage on a failed save, or half as much damage on successful one.
Most adventurers travel to the Nine Hells using either by portals or other means, but rarely do any travel through its gates seeking to stay as much away from its damned entrance. The Cerberus is the guarding overgrowing Hell Hounds of these gates; thus, they allowing none to pass except the unlucky dead.
The Three Headed Origin. The Cerberus are born when a previous Cerberus die during their guarding duty, the Hell Hound grow larger and spring two extra heads so that he became a three headed Cerberus. However, the Cerberus has a distinct hatred to its own kind, and would most likely attack any Hell Hound on sight due to some primal urge unless a common enemy exists within sight.