I Aboleths t is ordinary, perhaps even inevitable, that the intelligent races of the material plane imagine and investigate the circumstances of their species' origin, and the origin of their plane more broadly. Creation myths vary across cultures, but such disagreements are dismissed easily enough by those devoutly convinced of one story or another. The aboleths have no such creation myths. They do not speculate. They remember. They remember the arrival of each sapient species that has arisen on the material plane, along with the unremarkable extinction of the overwhelming majority of them. They remember mountains rising and crumbling, seas forming. They remember the creation of the gods themselves. Each of these is a mere passing curiosity to the aboleths, a dream melting into the ether. Each creation of this world will pass in time, and the aboleths will persist. The aboleths live in memory as much as they do in physical space, and in their memories they find the final repugnant truth of reality; that most creatures of this world are purposeless accidents, and those created with purpose are no better off, slaves to the meaningless whims of their creators. The aboleths have an alternative to offer. Their whims are far from meaningless. Aboleth Lore Arcana DC 15: As with creatures native to the outer planes, aboleths do not truly die when killed. Instead, they are born into a new aboleth body in the elemental plane of water. Arcana DC 20: Aboleths are powerful telepaths and can learn a creature's deepest desires through even the most casual telepathic communication. Their mind control abilities require concentration in the early phases of enslavement, but they have a way of discharging this need if given time. History DC 15: Aboleths are intelligent amphibious creatures that predate humanoid creatures in the material plane. They are known to have powerful mind control abilities. History DC 25: Aboleths report having no memory of the origin of the Ilithid race, leading some to theorize that the Ilithid are time travelers from some far future, perhaps even descendants of aboleths themselves, or a creation of theirs. Nature DC 15: Aboleths are coated in a slimy mucous that immediately begins to transform the bodies of creatures exposed to it, making them more suited to aquatic life as enslaved servitors. This disease can be cured only by magical means once it has taken hold. Nature DC 20: Larger, more powerful aboleths are able to mintuely control the pigmentation of their skin, making them extremely difficult to spot at a distance, particularly underwater. Nature DC 25: Despite their amphibious nature, an aboleth deprived of water will dry to a leathery texture over the course of 24 hours, entering a state of torpor called "The Long Dreaming" . Aboleths in this state can lay dormant for decades, returning to full vigor when submerged in water. Religion DC 15: Aboleths once ruled the world before the rise of gods, and hope to one day reclaim it. They hold the gods in extreme disdain. Religion DC 20: Aboleths have an eidetic memory, and pass down all of their memories to their offspring. They report recollections of events that predate all known creation myths, though religious scholars typically lend these assertions little credence.
Aboleth Hatchling Tactics The hatchling cannot effectively defend itself outside of its defensive telepathy, so if encountered alone will try to appear cute and nonthreatening, even friendly. When supporting a more mature aboleth, it uses its weaken mind on whichever PC the aboleth is going to target on the following turn, or attempts to dash out of harm's way otherwise. Aboleth Lasher Tactics Aboleths open engagements first socially, attempting to coax creatures into telepathic communication so they can learn and exploit their deepest desires, seeking either to gain voluntary service, or to lure the creatures into the water where they can be subdued and controlled. In combat, an aboleth opens with its Dominate ability against the PC with the lowest Wisdom saving throw, or against the one with the greatest faculty at fighting underwater. It will attempt to use its range, mucous and swim speed to stay out of melee range, taking attacks of opportunity if necessary. Early in the fight, the aboleth will attempt to infect whichever PC it is most interested in acquiring with its tentacles, ensuring that if the party retreats they must leave the aboleth's prize behind. Aboleth Behemoth Tactics Like the lasher, the behemoth wants to make use of its range and swim speed to protect it from melee attacks. Unlike the lasher, however, the behemoth the behemoth wants to lure the PCs into bunching up so it can affect as many of them as possible with its Tentacle Whirlwind, so rather than fleeing directly away it may be wiser to circle around, keeping backliners close with the threat of opportunity attacks and getting the frontliners to double back, ideally needing to dash to reach the aboleth. When its Reactive Camouflage triggers, the aboleth will usually flee. Aboleth Overseer Tactics The overseer wants to leave as much of the fighting to its dominated creatures as possible, and whenever it can will alternate between Dominate and Enslave while staying as far away from the fight as it can. If it feels like it has the fight in hand and is particularly interested in an acquisition, it may direct a Dominated and infected PC to swim into the deepest, darkest corner of its lair to prevent the possiblity of the party freeing them, particularly if the party can not breathe underwater. Aboleth Mindtaker Tactics The mindtaker combines traits and tactics of the behemoth and overseer. It prefers to let its servitors do most of the fighting for it, but will stay close enough that it can dive into combat if it sees a good opportunity to use its tentacle whirlwind. Encounter Groups A typical encounter might include an Aboleth Lasher and its coterie of ensnared adventurers; or an Aboleth Overseer, the kuo-toa that worship it, and a Chuul servitor. CR 11 Encounter 3,350 XP 1 Aboleth Lasher (CR 6) 1 Warlock Initiate (CR 2) 1 Barbarian Initiate (CR 1) 1 Bard Initiate (CR 1) 1 Rogue Initiate (CR 1) CR 19 Encounter 8,000 XP 1 Aboleth Overseer (CR 10) 1 Chuul (CR 4) 3 Kuo-Toa Cutters (CR 1) 2 Kuo-Toa Drowners (CR 1) Aboleth Hatchling Tiny aberration, lawful evil Armor Class 14 Hit Points 7 (1d10 + 1) Speed fly 20 ft., swim 20 ft. STR DEX CON INT WIS CHA 3 (-4) 9 (-1) 12 (+1) 18 (+4) 15 (+2) 18 (+4) Skills Perception +4 Senses Darkvision 120 ft, Passive Perception 14 Languages Deep Speech, Telepathy 120 ft Challenge 1 (200 XP) Amphibious. The aboleth can breathe air and water. Defensive Telepathy. A creature that attempts to harm the hatchling must succeed on a DC 14 Wisdom saving throw or be Charmed by the hatchling for the next minute. A creature Charmed by the hatchling has disadvantage on Wisdom saving throws. Actions Weaken Mind. One creature within 30 ft. that the hatchling can see must make a DC 14 Charisma saving throw. On a failure, the target must roll a d4 and subtract it from the total of the next saving throw it makes before the end of the hatchling's next turn.
Aboleth Lasher Large aberration, lawful evil Armor Class 17 Hit Points 135 (18d10 + 36) Speed 10 ft., swim 40 ft. STR DEX CON INT WIS CHA 21 (+5) 9 (-1) 15 (+2) 18 (+4) 15 (+2) 18 (+4) Saving Throws CON +6, INT +5, WIS +6 Skills Perception +10 Senses Darkvision 120 ft, Passive Perception 20 Languages Deep Speech, Telepathy 120 ft Challenge 6 (2,300 XP) Amphibious. The aboleth can breathe air and water. Mucous Cloud. While underwater, the area in a 10 foot radius around the Aboleth counts as difficult terrain for non-aberrations. Probing Telepathy. If a creature communicates telepathically with the aboleth, the aboleth learns, in broad terms, the creature's greatest desires. Actions Multiattack. The aboleth makes three tentacle attacks. It may replace one of these with a use of its compel. Tentacle. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 12 (2d6 + 5) bludgeoning damage and the target must make a DC 14 Constitution saving throw or become diseased. A diseased creature can only breathe water and can't regain hit points while outside of water. After 1 minute, a diseased creature's skin begins to turn slimy and translucent. A creature that fails this save by 5 or more gains vulnerability to the next source of bludgeoning damage it takes in the next minute. Compel. One creature charmed by the aboleth makes a weapon attack or casts a cantrip, targeting a creature of the Aboleth's choice. Dominate (Recharge 5-6, concentration). 30 ft. range, targets 1 creature the aboleth can see. The target must succeed on a DC 14 Wisdom saving throw or be magically charmed and under the aboleth's control. Whenever the charmed target takes damage, the target can repeat the saving throw, ending the effect on a success. Aboleth Behemoth Huge aberration, lawful evil Armor Class 17 Hit Points 190 (20d10+80) Speed 10 ft., swim 40 ft. STR DEX CON INT WIS CHA 23 (+6) 9 (-1) 18 (+4) 18 (+4) 15 (+2) 18 (+4) Saving Throws CON +9, INT +6, WIS +7 Skills Perception +10, Stealth +7 Senses Darkvision 120 ft, Passive Perception 20 Languages Deep Speech, Telepathy 120 ft Challenge 10 (5,900 XP) Amphibious. The aboleth can breathe air and water. Probing Telepathy. If a creature communicates telepathically with the aboleth, the aboleth learns, in broad terms, the creature's greatest desires. Actions Multiattack. The aboleth makes four tentacle attacks. Tentacle. Melee Weapon Attack: +10 to hit, reach 15 ft., one target. Hit: 16 (3d6 + 6) bludgeoning damage and the target must make a DC 16 Constitution saving throw or become diseased. A diseased creature can only breathe water and can't regain hit points while outside of water. After 1 minute, a diseased creature's skin begins to turn slimy and translucent. A creature that fails this save by 5 or more gains vulnerability to the next source of bludgeoning damage it takes in the next minute. Tentacle Whirlwind (Recharge 5-6). Each creature in a 15 foot radius around the aboleth must succed on a DC 16 Dexterity saving throw or take 35 (10d6) bludgeoning damage and be shoved 20 feet back, or take half as much damage on a success. Reactions Reactive Camoflauge (1/day). As a reaction to being reduced below 50 hit points, the aboleth becomes invisible to creatures more than 30 feet away from it. This invisibility lasts for 1 hour, or until the aboleth regains any hit points.
Miniature Recommendation. Archvillain Games, Mini Monster Mayhem and Rocket Pig Games (pictured here) all have gorgeous sculpts available as STLs. WizKids has one in their Nolzur's line that is passable, though has the benefit of being more durable than a 3D printed model. Aboleth Servitor Template. The aboleth servitor template can be applied to any creature without proficiency in Wisdom saving throws. An aboleth servitor has: Creature Type The creature's type changes to aberration. Swim Speed The creature gains a swim speed equal to its movement speed. Water Breathing The creature gains the ability to breathe water and loses the ability to breathe air. Vulnerability The creature gains Vulnerability to Bludgeoning damage. Aboleth Overseer Huge aberration, lawful evil Armor Class 17 Hit Points 173 (18d10 + 74) Speed 10 ft., swim 40 ft. STR DEX CON INT WIS CHA 21 (+5) 9 (-1) 18 (+4) 18 (+4) 15 (+2) 18 (+4) Saving Throws CON +9, INT +6, WIS +7 Skills Perception +10 Senses Darkvision 120 ft, Passive Perception 20 Languages Deep Speech, Telepathy 120 ft Challenge 10 (5,900 XP) Amphibious. The aboleth can breathe air and water. Viscous Mucous. While underwater, the area in a 10 foot radius around the Aboleth counts as difficult terrain for non-aberrations. A creature affected by the mucous that attempts to make an attack other than its first on a turn must first make a DC 12 Strength saving throw. On a failure, the attack fails. Probing Telepathy. If a creature communicates telepathically with the aboleth, the aboleth learns, in broad terms, the creature's greatest desires. Actions Multiattack. The aboleth makes three tentacle attacks. It may replace one of these with a use of its Compel or its Dominate ability. Tentacle. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 12 (2d6 + 5) bludgeoning damage and the target must make a DC 16 Constitution saving throw or become diseased. A diseased creature can only breathe water and can't regain hit points while outside of water. After 1 minute, a diseased creature's skin begins to turn slimy and translucent. Compel. A creature charmed by the Aboleth makes a weapon attack or casts a cantrip targeting a creature of the aboleth's choice. Dominate (Concentration). 30 ft. range, targets 1 creature the aboleth can see. The target must succeed on a DC 16 Wisdom saving throw or be magically charmed and under the aboleth's control. Whenever the charmed target takes damage, the target can repeat the saving throw, ending the effect on a success. Enslave (Recharge 5-6). One creature charmed by the aboleth must succeed on a DC 16 Wisdom saving throw or take 55 (10d10) psychic damage, or half as much on a success. If this damage reduces the charmed creature to 0 HP, it gains 55 (10d10) hit points and the aboleth no longer requires Concentration to Dominate it.
Aboleth Mindtaker Overlord Gargantuan aberration, lawful evil Armor Class 19 Hit Points 370 (20d20 + 160) Speed 10 ft., swim 40 ft. STR DEX CON INT WIS CHA 24 (+7) 9 (-1) 26 (+8) 21 (+5) 15 (+2) 18 (+4) Saving Throws CON +10, INT +11, WIS +8 Skills Perception +14, Stealth +11 Senses Darkvision 120 ft, Passive Perception 24 Languages Deep Speech, Telepathy 120 ft Challenge 20 (25,000 XP) Amphibious. The aboleth can breathe air and water. Viscous Mucous. While underwater, the area in a 10 foot radius around the Aboleth counts as difficult terrain for non-aberrations. A creature affected by the mucous that attempts to make an attack other than its first on a turn must first make a DC 16 Strength saving throw. On a failure, the attack fails. Probing Telepathy. If a creature communicates telepathically with the aboleth, the aboleth learns, in broad terms, the creature's greatest desires. Mindtaker Resilience (3/Day). If the aboleth fails a saving throw, it can choose to succeed instead. When it does, each creature dominated by the aboleth may make a DC 19 Wisdom saving throw at advantage, freeing itself on a success. Actions Multiattack. The aboleth makes four tentacle attacks. It may replace up to two of these with its Compel or Dominate abilities. Tentacle. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 19 (4d6 + 5) bludgeoning damage and the target must make a DC 22 Constitution saving throw or become diseased. A diseased creature can only breathe water and can't regain hit points while outside of water. After 1 minute, a diseased creature's skin begins to turn slimy and translucent. A creature that fails this save by 5 or more gains vulnerability to the next source of bludgeoning damage it takes in the next minute. Compel. One creature charmed by the Aboleth makes a weapon attack or casts a cantrip, targeting a creature of the aboleth's choice. Dominate (Concentration). 60 ft. range, targets 1 creature the aboleth can see. The target must succeed on a DC 19 Wisdom saving throw or be magically charmed and under the aboleth's control. Whenever the charmed target takes damage, the target can repeat the saving throw, ending the effect on a success. A creature that fails this save by 5 or more is additionally stunned until the end of its next turn. Enslave (Recharge 5-6). One creature Charmed by the aboleth must succeed on a DC 19 Wisdom saving throw or take 110 (20d10) psychic damage, or half as much on a success. If this damage reduces the Charmed creature to 0 hit points, it gains 110 (20d10) hit points and the aboleth no longer requires Concentration to Dominate it. Tentacle Whirlwind (Recharge 5-6). Each creature in a 15 ft. radius must succed on a DC 22 Dexterity saving throw or take 49 (14d6) bludgeoning damage and be shoved 20 feet back, or half damage on a success. Reactions Reactive Camoflauge (1/day). As a reaction to being reduced below 100 hit points, the aboleth becomes invisible to creatures more than 30 feet away from it. This invisibility lasts for 1 hour, or until the aboleth regains any hit points. Legendary Actions The aboleth can take 3 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 aboleth regains spent legendary actions at the start of its turn. Dive. The aboleth moves up to half its movement speed without provoking attacks of opportunity. If its Reactive Camoflauge is active, it may then attempt to Hide as part of this action. Compel. The aboleth uses its Compel ability. Mental Fog (Costs 2 Actions). One creature within 120 feet of the aboleth must make a DC 19 Intelligence saving throw. On a failed save, the target takes 14 (4d6) psychic damage and subtracts 1d6 from the next saving throw it makes before the end of the aboleth's next turn.
Art Credits Aboleth by Mark Behm Miniature by Rocket Pig Games Photograph/Mini Painted by Oh_Hi_Mark_ Bisk, Goblin King by Rae Elderidge I've Got a Subreddit! Want more monsters like this? Come check out r/bettermonsters, where I post all my work. Don't see something there? Drop a request and I'll usually get it to you within a day if I've got something on hand, and I'll shoot you a message when it's ready if not. You Found the Free Books! The Part Where I Shill My Patreon Want to support the creation of content like this? I post new monsters with lore and tactics to my patreon five times a week, joining the more than 1300 already there, indexed in a big PDF along with formats for Foundry and 5eTools.