Medium elemental, neutral evil

Armor Class 12 (description)
Hit Points 99 (18d8+18)
Speed fly 40 ft.

11 (+0) 15 (+2) 12 (+1) 13 (+1) 16 (+3) 15 (+2)

Skills Deception +5, Persuasion +5
Saving Throws Dexterity +5, Charisma +5
Damage Immunities cold, Lightning
Damage Resistances bludgeoning, piercing, and slashing from non-magical weapons
Senses passive Perception 13
Languages Common, Primordial
Challenge 5 (1,800 XP)


  • Innate Spellcasting. The elethu can innately cast lightning bolt 5 times per day (Save DC 15).


  • Slam. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 5 (1d10) bludgeoning damage.
  • Engulf. The creature can attempt to engulf any creature of size large or smaller. The target must make a Dexterity save (DC 16) to avoid the effect. An engulfed creature is considered restrained and automatically takes Slam damage each round. Further, if a creature has been engulfed for 1 round or more, the elethu can attempt its moonbeam transformation on them. Each round, the target may use its action to make either a Strength or Dexterity save (their choice) against a DC 16, escaping the engulf on a success.
  • Moonbeam Transformation. This can only be used on engulfed targets. The target must make a Constitution save (DC 15). On a failed save, the target is transformed into a beam of moonlight. It is unable to move, attack or communicate in this form. The target can repeat the save once per day at dawn. The effect can also be removed with a Dispel Magic or Greater Restoration.

The elethu are millions of strands of light, bound together by a powerful conscious. These creatures appear as beautiful women, with long hair, often reaching to their waist or beyond. Their skin is a silvery color as is their hair. The hair itself morphs into a very long gown that trails behind the creature or levitates around it. They do not walk as much as float over the ground. When angered, their form changes, shifting into something that far more resembles a living cloak than that of a woman.

Reclusive. The elethu love water and seek it out whenever they can. They often build their dens beneath the water or at least in caves and hidden grottos. They are solitary creatures and do not readily seek anyone’s company. They do not speak any language known to man, magical or otherwise. They see most living creatures as disturbances only and have little if anything to do with them.

Hatred of Light. While elethu are creatures of light, they are also jealous of all other light, seeking to be the only light in an area. The best way to elicit a response from an elethu is to enter its den with any light source, natural or magical. The sight of this enrages them and they attack whoever bears the torch, lantern, or magical flame. Spell-like effects can garner this response, such as a faerie fire, light spell, and so forth. Normal magical swords that emanate a muted light do not. When enraged, elethus shed their female forms, shifting into a billowing curtain of light. They use their lightning strike to kill whoever angers them, usually the torchbearer.

Section 15: Copyright Notice

5th Edition Monsters & Treasure of Airhde, 1st Printing, Copyright 2021, Troll Lord Games; Author Stephen Chenault & Jason Vey

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