Huge aberration, chaotic evil

Armor Class 18 (natural armor)
Hit Points 507 (35d12+280)
Speed 30 ft., swim 50 ft.

24 (+7) 29 (+9) 27 (+8) 16 (+3) 23 (+6) 22 (+6)

Saving Throws Dex +16, Con +15, Cha +13
Skills Acrobatics +16, Deception +20, Insight +13, Intimidation +13, Perception +13
Damage Resistances fire; bludgeoning, piercing, and slashing from nonmagical attacks
Condition Immunities charmed, prone
Senses truesight 60 ft., blindsight 200 ft., passive Perception 28
Languages Abyssal, Aquan, Common
Challenge 23 (62,000 XP)

Special Traits

  • Amphibious. The scylla can breathe water and air.
  • Innate Spellcasting. The scylla’s spellcasting ability is Wisdom (spell save DC 21). It can innately cast the following spells, requiring no material components:
  • Legendary Resistance (3/Day). If the Scylla fails a saving throw, it can choose to succeed instead.
  • Magic Resistance. The scylla has advantage on saving throws against spells and other magical effects.
  • Multi-Headed. While the scylla can see in all directions, and has advantage on Wisdom (Perception) checks, which applies to its passive Perception score. It also has advantage on saving throws against being blinded, deafened, stunned, and knocked unconscious.


  • Multiattack. The scylla can use its frightful presence. It then makes three slam or tentacle attacks. It may substitute a bite for one of those attacks. In humanoid form, it may instead make three weapon attacks.
  • Bite. Melee Weapon Attack: +16 to hit, reach 15 ft., one grappled target. Hit: 27 (4d8 + 9) piercing damage, and 18 (4d8) necrotic damage, and the target can’t regain hit points until the end of its next turn.
  • Tentacle. Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 31 (4d10 + 9) bludgeoning damage, and the target is grappled (escape DC 22). Until this grapple ends, the target is restrained. The scylla has eight tentacles, each of which can grapple one target.
  • Poisoned Dagger (humanoid form only). Melee or Ranged Weapon Attack: +16 to hit, reach 5 ft. or range 20/60 ft., one creature. Hit: 11 (1d4+9) piercing damage, and 18 (4d8) poison damage.
  • Frightful Presence. Each creature of the scylla’s choice that is within 100 feet of the Scylla and aware of it must succeed on a DC 21 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 scylla’s Frightful Presence for the next 24 hours.
  • Change Shape. The scylla magically polymorphs into a Small or Medium female humanoid, or back into her true form. The scylla loses its bite and tentacle attacks but can wield weapons or make slam attacks as appropriate for its form. Its statistics are otherwise the same in each form. Any equipment it is wearing or carrying isn’t transformed. She reverts to her true form if she dies.

Legendary Actions

The scylla can take 2 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 scylla regains spent legendary actions at the start of its turn.

  • Tentacle. The scylla makes one attack with its tentacle.
  • Bite (Costs 2 actions). The scylla makes one attack with its bite.
  • Spell (Costs 2 actions). The scylla uses one of its spells.


The scylla is one of the more nightmarish aberrations to blight the mortal world, horrifying creatures with the upper body of a beautiful woman but a lower body of snapping wolf or serpent heads and writhing tentacles. Conflicting tales of her origins abound, from demonic flesh-crafting and arcane experiments to a divine curse handed down by a vengeful deity. The most popular stories cast the first scylla as the monstrous spawn of a union between a mortal and a god.

Whatever the case, scyllas are fortunately quite rare, enough so that many consider them nothing more than tall tales told by sailors deep in their cups.

Ship-Hunter. Scyllas dwell along major shipping lanes, often near coastlines, where they use their spells to lure entire ships to their doom. The hideous monsters are intelligent creatures, though half-mad with hunger and self-loathing. They normally do not use weapons, but when they do, they prefer to fight with light weapons wielded by their human-sized upper arms.

However, they much prefer to keep their hands free to utilize magic items like wands, staves, and other powerful devices.

Section 15: Copyright Notice

Sea Monsters (5E) © 2021, Legendary Games; Authors Michael Ritter, Michael “solomani” Mifsud, Robert J. Grady, Mark Hart, Jeff Ibach, Alex Riggs, Scott D. Young, Jeff Lee, Matt Kimmel, and Jason Nelson.

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