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Aboleth Behemoth

Aboleth Behemoth CR 16 (Combatant)

XP 76,800
LE Gargantuan aberration (aquatic)
Init +0; Senses darkvision 60 ft.; Perception +28
Aura mucus cloud (30 ft.)


HP 300
EAC 30; KAC 32
Fort +18; Ref +18; Will +16
Defensive Abilities barbs, uncrushable; DR 10/piercing or slashing; Immunities cold


Speed 20 ft., swim 80 ft.
Melee gore +30 (6d10+26P), or tentacle +30 (6d10+26B plus slime)
Multiattack 4 tentacles +24 (3d10+26B plus slime)
Space 20 ft.; Reach 20 ft. (40 ft. with tentacles)
Offensive Abilities ferocious charge
Spell-Like Abilities (CL 16th)

At willarcing surge (DC 19), holographic image IV (DC 20)
3/dayholographic terrain (DC 21), mislead (DC 21), synapse overload (DC 21), unwilling guardian (DC 21)
1/daychain surge (DC 22), veil (DC 22)


Str +10; Dex +0; Con +7; Int +0; Wis +3; Cha +5
Skills Athletics +33, Intimidate +28, Survival +28
Languages Aboleth, Aklo, Aquan; telepathy 100 ft.
Other Abilities water breathing


Barbs (Ex)

An aboleth behemoth’s hide is studded with black barbs the size of shortswords. Any creatures grappling the aboleth behemoth take 3d10+16 points of slashing damage per round, and must make a successful DC 22 Athletics or Sleight of Hand check to be able to release the aboleth behemoth.

Mucus Cloud (Ex)

While underwater on in microgravity, an aboleth behemoth exudes a cloud of transparent slime. All creatures in the aura of the mucus cloud must make a DC 22 Fortitude save or lose the ability to breathe air while gaining the ability to breath water for the next three hours. Renewed contact with the mucus cloud requires another save, with each failure extended the duration for three hours. Sealed environmental suits prevent the need to make a save.

Slime (Ex)

A creature hit by an aboleth behemoth’s tentacle while not fully sealed in an environmental suit must succeed at a DC 22 Fortitude save or have their skin and flesh transform into a clear, slimy membrane over the course of 1d4 rounds. The creature’s new “flesh” is soft and tender, reducing its Constitution score by 4 as long as it persists. If the creature’s flesh isn’t kept moist, it dries quickly; the victim gains water dependency as a weakness. Remove affliction and similar effects can restore an afflicted creature to normal, but immunity to disease offers no protection from this attack.

Uncrushable (Ex)

An aboleth behemoth is both study and flexible. It only takes half damage from attacks that deal bludgeoning or constricting damage.


Environment any aquatic
Organization Solitary or pair

Imagine a shark. This creature is the perfect predator; swimming through the ocean, using its finely-tuned senses to track down potential prey. It is an apex predator; existing at the top of the food chain.

Imagine a shark that could think… Imagine this same creature possessing a mind so keen and wicked that it could hone its will and force others to succumb to its very thoughts. This creature is called an aboleth.

Aboleths appear to be massive fish-like creatures with a trio of eyes and two pairs of long, manipulative tentacles. These creatures measure over 20 feet long and weigh 6,500 pounds (650 bulk). Their bodies produce a foul-smelling slime that permeates the water surrounding them at all times. This slime can be dangerous to those creature to which in come in contact. Aboleths use this slime to create slaves from land-dwelling creatures. And keep them bound to their service. The slime has the ability to transform those it touches into creature that need to be constantly wet; forcing land-dwelling beings into the water.

Furthermore, anyone who inhales this slime is again transformed into a creature that needs water to breathe.

Besides their physical traits, aboleths have ancient minds with vast mental powers. They often hone their powers towards controlling the minds of others; transforming them into slaves to serve the lazy aberrations.

All of these physical and mental traits are the result of millions of years of collected power with the aboleths. They claim to be older than any other mortal species and some even dare to be older than the gods themselves. Aboleths have kingdoms in the depths of numerous ocean worlds and even in the sunless lakes and seas found underground on other worlds. Many of these areas have structures that are millions of years old, giving credibility to the boasts of the aboleths.

Aboleth behemoths are genetically-engineered living war machines created by the aboleth.

Originally designed to battle kraken, these massive horrors appear to be multi-tentacled monstrosities in the vague shape of an aboleth. Their bodies are covered in a thick, sharp substance; giving them the appearance of an animate coral reef. The behemoth’s trio of eyes are protected by a massive pair of bull-like horns.

Section 15: Copyright Notice

Starfarer Adversaries: Legacy Bestiary © 2020, Rogue Genius Games LLC; Author: Jacob E. Blackmon; Additional work by: Owen K.C. Stephens. Produced by Owen K.C. Stephens.