Aboleth and Skum

by mshrm

I remember the first time I opened up the 1st Edition AD&D Monster Manual II and came face-to-face with the aboleth. Really, who can resist a psionic eel who lives in subterranean caves plotting revenge for ancient losses, but just can’t bring themselves to crawl out of their holes and leave their slave-driven comfort behind?

Of course, long before you meet the aboleth, you’ll meet hordes of skum.  They’re brutish fish-men with claws. The aboleth breed them and keep them as slaves. Their origins are murky and unpleasant, but it’s generally assumed that the aboleth created them from samples of other humanoid races.

Skum are textbook humanoid mooks, just with the ability to function in the water. Whenever possible, they’ll try to drag the battle into deep water. Since they’re rarely found away from the lairs of their masters, deep water is generally handy.



ST: 18

HP: 18

Speed: 5.75

DX: 12

Will: 10

Move: 5

IQ: 10

Per: 12

HT: 11

FP: 11

SM: +0

Dodge: 8


DR: 2

  • Claw (12) 1d+1 cut, reach C

  • Rake (10) 1d+2 cut, reach C, 1. When fighting in the water, they like to grapple with their arms and bite, and rake with their back legs.

  • Bite (12): 1d+1 cut, reach C


Amphibious; Appearance (Ugly); Bad Temper (12); Dark Vision; Doesn’t Breathe (Lungs and Gills); Sharp Claws; Sharp Teeth; Social Stigma (monster)


Observation 11, Stealth 11, Swimming 13

Once the delvers have fought their way through an endless supply of skum, they might meet their aboleth master. Probably not, though…



ST: 33

HP: 33

Speed: 6.25

DX: 11

Will: 18

Move: 6 water, 1 ground

IQ: 15

Per: 15

HT: 14

FP: 14

SM: +4 (6500 lbs)

Dodge: 9

Parry: 8 (unarmed)

DR: 6 (tough skin)

  • Tentacle Strike (11): 3d+1 cr, reach C,1-3, plus affliction

  • Aboleth Affliction (aura) If touched on bare skin (Contact Agent) by a tentacle, resist with HT-3 or skin becomes a moist, semi-transparent membrane; victim gains Fragile (Brittle), Unnatural Feature, and Weakness (drying out, 1d/5 min). The aboleth can turn this power on and off.

  • Bite (11) 3d-5 cr, reach C

  • Mind Control (IQ vs Will) Psionic version of the Mind Control advantage with the Puppet limitation. Those controlled gain Slave Mentality.

  • Hypnotic Pattern (18) Psionic power that projects a Persistent Sense-Based (vision) Malediction over a 4 yard radius. Those in the area who see the pattern must roll Will or become Stunned (roll Will to recover).

  • Veil of Illusion (18) Psionic power that projects a Malediction on the target (-1/yd range). Victim must roll Will-3 or be Afflicted with a Cosmetic Morph to appear as the aboleth wishes for 1 minute times the margin of failure.

  • Suffocating Mucus (aura) In water, the aboleth is always surrounded with a layer of mucus. Any who come into contact with this mucus with their bare skin must roll vs HT-3 or trade the ability to breathe air for the ability to breathe water for 30 minutes times the margin of failure.

  • Magical Mirage: Psionic power of Illusion over an 16yd radius with Independence. Used to create illusory walls or floors, or to change the appearance of an area.

  • Programmed Illusion: Psionic power of Illusion over a 4yd radius with Initiative, so it can be programmed to react to external stimuli.


Amphibious; Appearance (Horrific); Callous; Charisma 3; Clairsentience (Projection, can use spells, psi, and Maledictions on the physical world, Increased Range x20, Reduced Time x2, Visible, Psionic: 15 sec to activate, range 200yd); Dark Vision; Doesn’t Breathe (Lungs & Gills); Double-Jointed; Extra Arms 2; Fanaticism (Aboleth superiority); Hard to Kill 2; Laziness; No Legs (Semi-Aquatic); Psi Talent 4; Telecommunications (Telesend, Psionic); Racial Memory (Active); Resistant to Metabolic Hazards +3; Social Stigma (Monster); Weak Bite


Artist (Illusion) 15; Fast Talk 15; Hidden Lore (any one) 16; Intimidation 21; Observation 14; Wrestling 14


Aboleth; plus, any two at Native level


An aboleth is clearly a boss monster. They have the power and inclination to reshape their environment through illusions. These aren’t magical illusions, either. They’re psionic, meaning the average delving band isn’t going to be set up as well to handle them as they otherwise might be.

An established lair will be a maze of passages hidden behind false walls and holes concealed under illusory floors. They can use their powers to conceal traps set up by their mind-controlled slaves. The party that makes it past the skum might have trouble figuring out where to go from there, and will likely take a certain amount of damage just from walking around the lair.

When they finally find the aboleth, well… it’s probably just a programmed illusion, left with a script to taunt intruders. It doesn’t cost the aboleth much beyond thinking of the script to set up these illusions, so there’s likely to be more than one. To say the least.

Eventually, the party might be “lucky” enough to find an aboleth that isn’t an illusion. They’ll know, because this one will start throwing around psionic devastation. It’ll use mind control to turn members of the party against each other. It’ll cast illusions to change the appearance of the wearer-willed members to sow confusion among the attackers. It’ll set up zones of hypnotic illusions to disrupt their minds.

Still not the aboleth. They can project their minds to remote locations through advanced psionic powers. (See GURPS Powers, page 44, the “Projection” box.) They can use their natural psionic abilities through these projections, despite being immaterial. Individual aboleth who have studied the ways of magic can use their spells, as well. (Oh, yeah, some of them study magic, too. Obviously, right?) They’re only vulnerable to similar forces.

If a party manages to wade through all of these and corner the real, actual, physical aboleth… that’s when the trouble really starts. Aside from all the psionic powers displayed by their projections, they’re also huge eel-like creatures with four powerful tentacles. Their touch causes humanoids’ skin to change into a semi-transparent membrane that must be kept moist.

Like their skum minions, they’re comfortable into the water. Any adventurer unfortunate enough to come into bare-skinned contact with an aboleth in the water will be transformed by the mucus they secrete, losing the ability to breathe air, but gaining the power to breathe water. A favorite aboleth trick is to establish an air-filled lair at the end of a long water-filled tunnel. They can bring in air-breathing slaves, temporarily transformed by their mucus. Any slave attempting to leave without the company of an aboleth will be faced with a swim far beyond the capacity of their lungs.