Demon Lord, Father of Monsters

Family: Demons

Gargantuan fiend (demon), chaotic evil

Armor Class 21 (natural armor)
Hit Points 314 (17d20 + 136)
Speed 50 ft., burrow 50 ft., fly 90 ft.

30 (+10) 14 (+2) 26 (+8) 17 (+3) 22 (+6) 19 (+4)

Saving Throws Dexterity +9, Constitution +15, Wisdom +13, Charisma +11
Skills Arcana +10, Deception +11, Intimidation +11, Perception +13
Damage Resistances cold, fire, lightning
Damage Immunities poison; bludgeoning, piercing, and slashing from nonmagical attacks
Condition Immunities charmed, exhaustion, frightened, poisoned
Senses truesight 120 ft., passive Perception 23
Languages all, telepathy 120 ft.
Challenge 22 (41,000 XP)

Special Traits

  • Legendary Resistance (3/day). If the Father of Monsters fails a saving throw, he can choose to succeed instead.
  • Magic Resistance. The Father of Monsters has advantage on saving throws against spells and other magical effects.
  • Magic Weapons. The Father of Monster’s weapon attacks are magical.
  • Innate Spellcasting. The Father of Monster’s innate spellcasting ability is Charisma (spell save DC 19, +11 to hit with spell attacks). He can innately cast the following spells, requiring no material components:


  • Multiattack. The Father of Monsters makes three attacks: two with his snake bites and one with his or Enthralling Touch.
  • Snake Bites. Melee Weapon Attack: +17 to hit, reach 15 ft., one target. Hit: 23 (3d8 + 10) piercing damage and the target must succeed on a DC 23 Constitution saving throw or be poisoned for 1 minute. While poisoned in this way, the creature takes 11 (2d10) poison damage at the start of its turn. A poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
  • Tail. Melee Weapon Attack: +17 to hit, reach 20 ft., one creature. Hit: 26 (3d10 + 10) bludgeoning damage and the target is grappled (escape DC 20) if it is a Large or smaller creature. Until this grapple ends, the creature is restrained. The Father of Monsters has two tails, each of which can grapple only one target.
  • Enthralling Touch. Melee Spell Attack: +11 to hit, reach 15 ft., one creature. Hit: The target is magically cursed. Until the curse ends, the target has disadvantage on Wisdom saving throws and all ability checks. The curse lasts until removed by the remove curse spell or other magic.

Legendary Actions

The Father of Monsters can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The Father of Monsters regains spent legendary actions at the start of his turn.

  • Snake Bites. The Father of Monsters makes one snake bites attack.
  • Enthrall. The Father of Monsters makes one enthralling touch attack.
  • Wing Attack (Costs 2 Actions). The Father of Monsters beats his wings. Each creature within 15 feet of the Father of Monsters must succeed on a DC 25 Dexterity saving throw or take 17 (2d6 + 10) bludgeoning damage and be forced prone. The Father of Monsters can then fly up to half his flying speed.


The creature towers out of a nightmare. It is humanoid from the waist up and serpentine from the waist down with its lower body splitting into two tails. Great scaled, leathery wings sprout from its shoulders, and its arms fork into nests of hissing snakes just below the elbow. Its eyes are baleful flames, casting ugly shadows into its wild hair and beard.

This towering demon lord lives in bitter exile, chained to his level of the Abyss by defeat in an ancient conflict against the powers of good. He broods in the depths of his cavern, hoarding stolen wealth and spawning ever more hideous creatures to unleash upon the multiverse.

Desperate for Escape. While most demon lords can’t easily leave their demesnes within the Abyss for various reasons, The Father of Monster’s very essence is bound beneath his mountain by the powers of heaven. No known portal, spell, ritual, or even divine intervention yet attempted can release him. His influence can slip through the cracks in the planes in the form of his demons and spawn, but the Father of Monsters himself can find no such release. He is obsessed with finding the key to his prison and will spare no amount of effort nor show a shred of mercy in pursuit of the solution.

Eyes, Ears, and Claws. Of all the creatures that crawl into existence under The Father of Monster’s corrupted touch, his favorites are the lamia.

Conventional demonology holds the lamia were created by a different demon lord originally, but the Father of Monsters delights in subverting that supposed truth. Lamia created or blessed by the Father of Monsters vary from the expected norm of a lower leonine body and sport a variety of bestial lower bodies. Snake tails are the most common, but the lower bodies of boars, crocodiles, sharks, and even spiders have been reported.

Many lamia abroad in the planes are servants of the Father of Monsters, actively seeking out information and power that might free their master from his prison. Besides the lamia, the Father of Monsters employs other spies that can often slip into places demons and monstrosities can’t. Many planar explorers meet their end after being spared the Father of Monsters’s fangs and pressed into his service to search out and steal some celestial artifact or demonic power that might lead to his release.


The Father of Monsters rules a layer of the Abyss covered in dense forests and rocky hills that radiate out from a singular mountain. Within the mount is a honeycomb of tunnels and immense caverns that the Father of Monsters fills with beautiful treasure and hideous horrors. Monsters of all kinds spring up in the shadow of The Father of Monster’s wings. The creatures lurk in the halls and spill out to seek portals to the Material Plane.

Lair Actions

On initiative count 20 (losing initiative ties), the Father of Monsters takes a lair action to cause one of the following effects; the Father of Monsters can’t use the same effect two rounds in a row:

  • The Father of Monsters creates a creature at a point he can see within the lair. A single aberration, dragon, monstrosity, or ooze of challenge rating 10 or less or a demon of challenge rating 5 or less crawls out of a crack in the ground. It acts immediately and on initiative count 20 on subsequent rounds. The creature follows the Father of Monsters’s commands and remains for 1 hour or until the Father of Monsters uses this lair action again.
  • The Father of Monsters howls, causing blood-curdling echoes to reverberate through the lair. All the Father of Monster’s enemies within 300 feet that can hear the howl must succeed on a DC 15 Wisdom saving throw or be frightened until the end of its next turn.
  • The Father of Monsters causes chains of rock to burst out of the ground, ceilings, or wall. Two creatures that the Father of Monsters can see within 120 feet of him must succeed on a DC 15 Strength saving throw or be restrained by the chains until initiative count 20 on the following round. A creature can be freed if it or another creature takes an action to make a DC 15 Strength check and succeeds. The chains crumble to dust if the creature is freed.

Regional Effects

The region containing the Father of Monsters’s lair creates one or more of the following effects:

  • Within 5 miles of the lair, aberrations, beasts, dragons, monstrosities, and oozes are extremely common and highly aggressive.
  • The Father of Monsters can communicate telepathically with any lamia within 5 miles of the lair.
  • Clouds grow thick in the sky within 1 mile of the lair. Even in broad daylight the area is only dim light. Inside the lair itself, all light sources have their illumination radius reduced to half.

If the Father of Monsters dies, these effects fade over the course of 1d10 days.

Section 15: Copyright Notice

Creature Codex. © 2018 Open Design LLC; Authors Wolfgang Baur, Dan Dillon, Richard Green, James Haeck, Chris Harris, Jeremy Hochhalter, James Introcaso, Chris Lockey, Shawn Merwin, and Jon Sawatsky.

This is not the complete section 15 entry - see the full license for this page