Greater Aboleth — Overseer of the Drowned Slave-Cities
A larger, older aboleth bred to control slaves, police submerged cities and break resistance before it reaches the ruling castes.
The greater aboleth is not simply a common aboleth with more hit points. In the old aboleth hierarchy it is an overseer: a creature entrusted with slave populations, punishment, breeding programmes and the day-to-day maintenance of a drowned city’s labour force. Common aboleths gather captives. Greater aboleths turn those captives into a stable system.
At a Glance
Run It Tonight
Do not introduce a greater aboleth alone in an empty cavern. Its encounter should begin before the monster is visible: enthralled scouts give misleading directions, doors open because a slave has been ordered to betray the party, and illusions turn safe water into apparent stone or conceal the real channel. When the greater aboleth finally enters the fight, it should already know who is easiest to dominate and who must be dragged underwater first.
Rules by Edition
Greater Aboleth
Gargantuan Aberration, typically Lawful Evil
AC 18; Initiative +0 (10)
HP 451 (26d20 + 208)
Speed 10 ft., Swim 60 ft.
24 (+7)
10 (+0)
26 (+8)
28 (+9)
20 (+5)
28 (+9)
Saving Throws Str +13, Con +14, Int +15, Wis +11, Cha +15
Skills Arcana +15, Deception +15, History +15, Insight +11, Perception +11
Immunities Psychic; Charmed, Frightened
Senses Blindsight 120 ft., Darkvision 120 ft.; Passive Perception 21
Languages Deep Speech; telepathy 500 ft.
CR 18 (20,000 XP); PB +6
Traits
Amphibious. The greater aboleth can breathe air and water.
Legendary Resistance (3/Day). If the greater aboleth fails a saving throw, it can choose to succeed instead.
Mucus Cloud. While underwater, the greater aboleth is surrounded by mucus in a 15-foot Emanation. A creature that ends its turn there must succeed on a DC 22 Constitution saving throw or become afflicted. While afflicted, it can breathe underwater but can’t regain Hit Points unless submerged, and it takes 13 (2d12) Acid damage at the end of each of its turns while dry. Greater restoration, heal or comparable magic ends the affliction.
Probing Telepathy. A creature that willingly communicates telepathically with the greater aboleth reveals its strongest current desire unless it succeeds on a DC 23 Wisdom saving throw.
Actions
Multiattack. The greater aboleth makes three Tentacle attacks. It can replace one attack with Enslave.
Tentacle. Melee Attack Roll: +13, reach 20 ft. Hit: 21 (3d8 + 8) Bludgeoning damage, and a Large or smaller target is Grappled (escape DC 21). A creature hit must also succeed on a DC 22 Constitution saving throw or contract the greater aboleth’s slime affliction after 1 minute.
Tail. Melee Attack Roll: +13, reach 15 ft. Hit: 19 (2d10 + 8) Bludgeoning damage.
Enslave (3/Day). One creature the greater aboleth can see within 60 feet makes a DC 23 Wisdom saving throw. On a failure, the target has the Charmed condition for 24 hours and obeys the aboleth’s telepathic commands. It repeats the save whenever it takes damage and once every 24 hours while more than 1 mile from the aboleth.
Psionic Command (Recharge 5–6). The greater aboleth targets up to three creatures it can see within 90 feet. Each makes a DC 23 Wisdom saving throw. On a failure, a target takes 27 (6d8) Psychic damage and must immediately use its Reaction, if available, to move up to its Speed in a direction chosen by the aboleth.
Legendary Actions
The greater aboleth can take three Legendary Actions, one at a time at the end of another creature’s turn.
Detect. The aboleth makes a Wisdom (Perception) check.
Tail. The aboleth makes one Tail attack.
Psychic Drain (Costs 2 Actions). One creature Charmed by the aboleth within 120 feet takes 14 (4d6) Psychic damage, and the aboleth regains the same number of Hit Points.
Greater Aboleth
Gargantuan aberration, lawful evil
Armor Class 18 (natural armor)
Hit Points 451 (26d20 + 208)
Speed 10 ft., swim 60 ft.
24 (+7)
10 (+0)
26 (+8)
28 (+9)
20 (+5)
28 (+9)
Saving Throws Str +13, Con +14, Int +15, Wis +11, Cha +15
Skills Arcana +15, Deception +15, History +15, Insight +11, Perception +11
Damage Immunities psychic
Condition Immunities charmed, frightened
Senses blindsight 120 ft., darkvision 120 ft., passive Perception 21
Languages Deep Speech, telepathy 500 ft.
Challenge 18 (20,000 XP)
Traits
Amphibious. The greater aboleth can breathe air and water.
Legendary Resistance (3/Day). If it fails a saving throw, it can choose to succeed instead.
Mucus Cloud. Underwater, creatures ending their turn within 15 feet must make a DC 22 Constitution saving throw or acquire translucent, water-dependent skin. Until cured by greater restoration, heal or comparable magic, an afflicted creature can breathe underwater, cannot regain hit points while dry, and takes 13 (2d12) acid damage at the end of each dry turn.
Actions
Multiattack. The greater aboleth makes three tentacle attacks and can replace one with Enslave.
Tentacle. Melee Weapon Attack: +13 to hit, reach 20 ft., one target. Hit: 21 (3d8 + 8) bludgeoning damage. A Large or smaller target is grappled (escape DC 21), and must succeed on a DC 22 Constitution saving throw or develop the slime affliction after 1 minute.
Tail. Melee Weapon Attack: +13 to hit, reach 15 ft., one target. Hit: 19 (2d10 + 8) bludgeoning damage.
Enslave (3/Day). One creature within 60 feet must succeed on a DC 23 Wisdom saving throw or be charmed for 24 hours and obey telepathic commands. The target repeats the save when damaged and once per day when more than 1 mile away.
Legendary Actions
Detect. The greater aboleth makes a Wisdom (Perception) check.
Tail. The greater aboleth makes one Tail attack.
Psychic Drain (Costs 2 Actions). One creature charmed by the aboleth within 120 feet takes 14 (4d6) psychic damage, and the aboleth regains the same number of hit points.
Greater Aboleth CR 16
XP 76,800
LE Gargantuan aberration (aquatic)
Init +5; Senses blindsight 120 ft., darkvision 120 ft.; Perception +30; Aura mucus cloud 20 ft.
Defense
AC 30, touch 7, flat-footed 29 (+1 Dex, +23 natural, −4 size)
hp 290 (20d8+200)
Fort +18, Ref +9, Will +19
DR 10/—; Immune cold, mind-affecting effects; Resist acid 20, electricity 20; SR 27
Offense
Speed 10 ft., swim 80 ft.
Melee 4 tentacles +24 (2d8+13/19–20 plus grab and slime), tail slap +24 (3d8+13)
Space 20 ft.; Reach 20 ft. (30 ft. with tentacles)
Special Attacks consume memories, enslave 3/day
Spell-Like Abilities CL 20th; concentration +29
At will—detect thoughts, levitate, major image, persistent image, project image, veil
3/day—dominate monster, mass suggestion, phantasmal killer
1/day—feeblemind, symbol of persuasion
Statistics
Str 36, Dex 12, Con 30, Int 24, Wis 20, Cha 28
Base Atk +15; CMB +32 (+36 grapple); CMD 43 (can’t be tripped)
Feats Combat Reflexes, Critical Focus, Improved Critical (tentacle), Improved Initiative, Improved Natural Attack (tentacle), Iron Will, Lightning Reflexes, Power Attack, Skill Focus (Perception), Spell Penetration, Weapon Focus (tentacle)
Skills Bluff +29, Diplomacy +29, Intimidate +32, Knowledge (arcana) +30, Knowledge (history) +30, Knowledge (nature) +30, Knowledge (planes) +30, Perception +30, Sense Motive +25, Spellcraft +30, Swim +44
Languages Aboleth, Aklo, Aquan, Common, Draconic, Undercommon; telepathy 500 ft.
Special Abilities
Consume Memories (Su). As a swift action against a creature it is grappling, the greater aboleth forces a DC 27 Will save. On a failure, it tears surface memories from the victim and deals 8d6 damage; on a success, damage is halved and no memories are learned. This is mind-affecting.
Enslave (Su). Three times per day, one creature within 120 feet must succeed on a DC 27 Will save or fall under a domination effect. The victim gains new saves after major injury and when separated from the aboleth for long periods.
Mucus Cloud (Ex). Underwater, a 20-foot cloud forces a DC 26 Fortitude save. Failure transforms the victim’s skin toward aquatic dependence; greater restoration or heal ends the effect.
Probing Telepathy (Su). Telepathic contact gives the greater aboleth an instinctive reading of the other creature’s fears and desires.
Ecology
Environment underground seas and abyssal trenches
Organization solitary or court with lesser aboleths and thralls
Treasure triple
Greater Aboleth
Huge Aberration (Aquatic)
Hit Dice 12d8+72 (126 hp)
Initiative +1
Speed 10 ft. (2 squares), swim 60 ft.
Armor Class 18 (−2 size, +1 Dex, +9 natural), touch 9, flat-footed 17
Base Attack/Grapple +8/+26
Attack tentacle +16 melee (1d8+10 plus slime)
Full Attack 4 tentacles +16 melee (1d8+10 plus slime)
Space/Reach 15 ft./10 ft.
Special Attacks bite, enslave, psionics, slime
Special Qualities amphibious, darkvision 60 ft., knowledgeable, mucus cloud, telepathy 60 ft.
Saves Fort +10, Ref +5, Will +14
Abilities Str 30, Dex 12, Con 22, Int 21, Wis 19, Cha 19
Environment underground
Organization solitary, brood (2–3), slaver brood, or city caste
Challenge Rating 11
Treasure double standard
Alignment usually lawful evil
Enslave (Su)
At will, a greater aboleth can attempt to enslave one living creature within 60 feet. The victim must succeed on a DC 23 Will save or become dominated. It gains another save every 24 hours and if separated from the aboleth by more than 5 miles.
Mucus Cloud (Ex)
Underwater, the greater aboleth surrounds itself with a thick mucus cloud. A creature inhaling it must succeed on a DC 21 Fortitude save or lose the ability to breathe air for 3 hours.
Slime (Ex)
A creature struck by a tentacle must succeed on a DC 21 Fortitude save or begin transforming over 1d4+1 minutes into a clear, slimy membrane that must be kept wet. Remove disease works before the transformation completes; afterward, heal or mass heal is required.
Psionics (Sp)
The legacy greater aboleth uses a broad suite of illusion and movement effects, including dimension door, hypnotic pattern, illusory wall, levitate, mirage arcana, persistent image, programmed image, project image, telekinesis and veil, with detect thoughts available three times per day.
Legacy Option: Oversized Maw
The older page also preserved an aboleth-specific feat allowing a Huge or larger aboleth with a powerful enough bite to swallow smaller creatures whole. Keep it as a 3.5e campaign option rather than treating it as a default Greater Aboleth ability.
What a Greater Aboleth Actually Does
The oldest hierarchy gives the greater aboleth a specific job: it receives slaves captured by common aboleths and maintains them inside the city. That means discipline, breeding, assignment of labour and suppression of revolt. Nobles conduct research. Rulers govern. Greater aboleths make the machinery of domination function every day.
This makes them excellent campaign villains because their influence can be encountered far from the monster itself. A fishing village can be serving an aboleth it has never seen. A mine may be sending selected captives down a flooded shaft. A noble’s household can contain generations of enthralled servants whose orders ultimately trace back to one creature beneath the earth.
Behaviour
A greater aboleth sees free will as a management problem. It would rather acquire a reliable servant than kill a useful enemy, and it spends time learning which desires, fears and loyalties make a target easiest to control. Violence is employed when it improves obedience or removes a variable that cannot be managed.
Unlike a common raider, it is reluctant to abandon a well-established slave network. If forced from its chamber, it retreats deeper into water while ordering thralls to close routes, destroy supplies or attack one another in ways designed to delay pursuit.
Signs Before Initiative
- Several unrelated people repeat the same unusual phrase or instruction word for word.
- A submerged gate has been repaired repeatedly by workers who have no obvious reason to maintain it.
- Captives are sorted by health, ancestry, trade or magical ability instead of being held randomly.
- Fresh water is stockpiled beside prisoners whose skin has become translucent and slick.
- Maps omit one flooded passage even though traffic marks show it is heavily used.
- Thralls protect an empty pool because the true entrance is beneath it.
If Violence Starts
The greater aboleth tries to win before trading tentacle attacks. It uses enslaved creatures to occupy the party’s attention, dominates anyone whose abilities would be more valuable on its side, and fights from water deep enough to make breathing and movement tactical problems.
When forced into direct combat it grapples high-value targets and drags them away from allies. It does not waste time killing a creature that can still be turned. Only targets resistant to control or threatening permanent destruction receive its full physical attention.
Counterplay
Breaking the slave network is often more important than damaging the aboleth. Freeing dominated lieutenants, exposing false memories and cutting telepathic command chains can remove most of the creature’s battlefield advantage before the final confrontation.
Dry ground helps, but the solution is not simply “fight it on land.” A greater aboleth plans around that weakness. Its chambers include flooded escape shafts, false floors, sluice gates and servants whose job is to restore water to a threatened area. Parties entering an aboleth city should treat control of water as seriously as control of doors.
The Aboleth Hierarchy
The legacy caste structure places common Aboleths at the gathering edge of the empire, Greater Aboleths above them as slave overseers, Noble Aboleths as researchers and travellers, and the Aboleth Ruler at the head of a city. Rumours of still greater specimens sit beyond even that hierarchy.
Using a Greater Aboleth in an Encounter
The quota. A common aboleth has stopped hunting after capturing exactly seven people. Something deeper is coming to collect them.
The perfect workforce. A flooded mine is producing impossible quantities of ore because the workers never sleep, never complain and never leave.
The breeding ledger. The party finds generations of records tracking families, magical traits and inherited resistances among a supposedly free lakeside population.
The dry rebellion. Escaped thralls have occupied the only dry chamber in an aboleth complex. The greater aboleth cannot reach them directly, so it sends people they still love.
Origins and Sources
The Greater Aboleth caste originates in “The Ecology of the Aboleth,” Dragon #131 (1988), where greater aboleths maintain slave populations inside aboleth cities and stand above common aboleths but below nobles and rulers. The 3.5e statistics preserved here descend from a later fan conversion formerly linked from the page.
Rules Sources and Licensing
The 5.5e/2024, 5e/2014 and Pathfinder 1e blocks are compatibility adaptations created for this entry from the legacy Greater Aboleth concept. They are not official statistics from those editions. The 3.5e block preserves the older conversion previously used on this page.
The original Greater Aboleth concept appeared in copyrighted Dragon magazine material. This page therefore paraphrases the caste lore rather than reproducing the original article text.