Armor Class 12
Hit Points 39 (6d8 + 12)
Speed 40 ft.
Skills Perception +5, Stealth +4
Damage Immunities fire, necrotic
Condition Immunities blinded, charmed, deafened, exhaustion, frightened, stunned
Senses darkvision 60 ft., passive Perception 15
Languages —
Challenge 2
Aggressive. As a bonus action, the cerberus can move up to its speed toward a hostile creature that it can see.
Multiheaded. The cerberus can't be surprised, and it has advantage on saving throws against being knocked unconscious.
Pack Tactics. The cerberus has advantage on an attack roll against a creature if at least one of the cerberus's allies is within 5 feet of the creature and the ally isn't incapacitated.
Multiattack. The cerberus makes two bite attacks.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) piercing damage plus 2 (1d4) fire damage.
Breath Weapon (Recharge 5–6). The cerberus exhales a 15-foot cone of molten rock. Each creature in the cone must make a DC 12 Dexterity saving throw, taking 10 (3d6) fire damage on a failed save, or half as much damage on a successful one. On a failed save, a creature is also restrained by the hardening rock. A creature can make a DC 12 Strength (Athletics) check as an action, freeing itself or a creature within reach from the rock on a success. The rock has AC 17 and 10 hit points, and it is immune to fire, poison, and psychic damage.
Mythic Odysseys of Theros, p. 215