Gargantuan monstrosity, unaligned

Armor Class 18 (natural armor)
Hit Points 525 (30d20 + 210)
Speed 0 ft., swim 70 ft.

30 (+10) 11 (+0) 24 (+7) 3 (-4) 16 (+3) 11 (+0)

Saving Throws Str +17, Dex +7, Con +14
Skills Perception +10
Damage Resistances acid, cold, fire
Damage Immunities poison; bludgeoning, piercing, and slashing from nonmagical attacks
Condition Immunities poisoned, prone
Senses darkvision 120 ft., passive Perception 20
Languages telepathy 120 ft.
Challenge 23 (50,000 XP)


  • Amphibious. The afanc can breathe air and water.
  • Siege Monster. The afanc deals double damage to objects and structures.


  • Multiattack. The afanc makes two Claw attacks and one Bite attack.
  • Bite. Melee Weapon Attack: +17 to hit, reach 20 ft., one target. Hit: 37 (6d8 + 10) piercing damage. If the target is a Large or smaller creature, that creature is swallowed. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the afanc, and it takes 42 (12d6) acid damage at the start of each of the afanc’s turns. If the afanc takes 50 damage or more on a single turn from a creature inside it, the afanc must succeed on a DC 25 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of the afanc. If the afanc dies, a swallowed creature is no longer restrained by it and can escape from the corpse using 15 feet of movement, exiting prone.
  • Claw. Melee Weapon Attack: +17 to hit, reach 20 ft., one target. Hit: 24 (4d6 + 10) slashing damage.
  • Sea Swell (recharge 5-6). The afanc raises the front part of its body out of the water and brings it crashing back down against the surface. This generates massive waves up to 30 feet tall that may capsize boats and ships within 100 feet of the afanc. Boats and ships less than 20 feet long automatically capsize. A creature steering or guiding a boat or ship over 20 feet long must succeed on a DC 20 Dexterity or Strength check or its boat capsizes. A creature proficient in Vehicles (water) may add its proficiency bonus. A non-aquatic creature in the water within 100 feet of the afanc must succeed on a DC 20 Dexterity saving throw or take 21 (6d6) bludgeoning damage and be stunned until the end of its next turn.


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

  • Claw Attack. The afanc makes one Claw attack.
  • Move. The afanc moves up to half its speed.
  • Roll (costs 2 actions). The afanc does a full body roll, sending up a spray of obscuring water in a 60-foot radius around it. That area is heavily obscured to creatures other than the afanc until the end of the afanc’s next turn.


Afancs are the sea monsters sailors talk about when spinning tales of the sea. They are the creatures responsible for entire fleets and crews being lost or destroyed. They are thought by many to be the “kings” of the sea as most other water-dwellers pale in comparison in strength and size to the mighty afanc. An afanc is generally about 100 feet long though specimens as large as 200 feet long are thought to exist. Its whale-like body is gray or sometimes bluish-green, although its eyes are always blue. Its tail is extremely long and ends in a truncated or flat, square edge. An afanc has a bulbous, somewhat flattened head, not unlike that of a great catfish. Afancs are omnivorous hunters of the deep sea that feed on a mixed diet of kelp, coral, sea plants, sharks, whales, various other large fishes, and swimmers and sailors unfortunate enough to cross their path.

Section 15: Copyright Notice

Tome of Horrors 2020, (C) 2020, Necromancer Games

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