Hellfire WyrmHuge dragon, lawful evilArmor Class 22 (natural armor)Hit Points 405 (30d12 + 210)Speed

Hellfire WyrmHuge dragon, lawful evilArmor Class 22 (natural armor)Hit Points 405 (30d12 + 210)Speed 50 ft., burrow 30 ft., fly 90 ft.Str 27, Dex 10, Con 25, Int 20, Wis 21, Cha 25Saving Throws Dex +8, Con +16, Wis +14, Cha +15Skills Deception +14, Perception +13Damage Immunities fire; bludgeoning, piercing, and slashing from nonmagical attacksDamage Vulnerabilities coldCondition Immunities paralyzedSenses passive Perception 23, truesight 120 ft.Languages Common, Draconic, InfernalChallenge 26 (90000 XP)Infernal Aura. At the start of each of the wyrm’s turns, each creature within 5 feet of it takes 10 (3d6) fire damage, and flammable objects in the aura that aren’t being worn or carried ignite. A creature that touches the wyrm or hits it with a melee attack while within 5 feet of it takes 10 (3d6) fire damage. The wyrm can suppress or resume this aura as a bonus action.Legendary Resistance (3/Day). If the wyrm fails a saving throw, it can choose to succeed instead.Magic Resistance. The wyrm has advantage on saving throws against spells and other magical effects.Innate Spellcasting. The hellfire wyrm’s spellcasting ability is Charisma (spell save DC 23). The hellfire wyrm can innately cast the following spells, requiring no material components:At will: charm person, hold person, sending, wall of fire1/day each: greater invisibility, meteor swarmActionsMultiattack. The wyrm can use its Frightful Presence. It then makes six attacks: one with its bite, four with its claws, and one with its tail.Bite. Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 27 (4d8+9) piercing damage plus 14 (4d6) necrotic damage.Claw. Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 18 (2d8+9) slashing damage plus 10 (3d6) necrotic damage.Tail. Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 21 (3d8+8) bludgeoning damage plus 10 (3d6) necrotic damage. If the target is a creature, it must succeed on a DC 24 Strength saving throw or be knocked prone.Fiendish Form. The wyrm magically polymorphs into a Small or Medium fiend, or back into its true form. Its statistics are the same in each form. Any equipment it is wearing or carrying isn’t transformed. It reverts to its true form if it dies.Frightful Presence. Each creature of the wyrm’s choice that is within 120 feet of the wyrm and aware of it must succeed on a DC 22 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature’s saving throw is successful or the effect ends for it, the creature is immune to the wyrm’s Frightful Presence for the next 24 hours.Hellfire Breath (Recharge 5-6). The wyrm exhales fire in a 50-foot cone. Each creature in the area must make a DC 23 Dexterity saving throw, taking 44 (8d10) fire damage and 44 (8d10) necrotic damage on a failed save, or half as much damage on a successful one.Summon Fiend (1/Day). The wyrm summons a horned devil, barbed devil, or bone devil to aid it in battle. The devil appears within 60 feet of the wyrm. Roll initiative for the devil, which has its own turns. It remains for 1 minute, or until dismissed by the wyrm as a bonus action. The devil obeys the wyrm’s orders, which it can issue at the start of each of its turns.These dread dragons are servants of the most powerful devils, even exceeding many of them in power. They often spend time in the form of a humanoid, manipulating rulers of nations into doing their bidding. Others rule as outright tyrants. In its true form, a hellfire wyrm’s eyes glow yellow, smoke billows constantly from its body, and it is surrounded by a sulfurous stench. Few creatures can stand up to a hellfire wyrm in combat, and in the rare instance the creature does find itself outmatched, it will retreat to one of its numerous secret lairs to plot its revenge.Originally from the Monster Manual II -- source link

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