According to Lords of Madness, the civilization of the aboleths is the most ancient in existence. The memories of these creatures stretch back to a time before time, and they can recall ancient evils that have long since faded from human knowledge. Only a few simple changes are needed to adapt this concept for use in an Eberron campaign.
The mythology of Eberron mentions a war that took place at the dawn of time. Most legends speak of the rakshasas as the first fiends and refer to them as the most ancient enemies of the light. But these creatures were not the only children of Khyber — the oceans became home to the aboleths at about the same time as the first rakshasas were created. The rakshasas ruled the land, but the aboleths held sway in the deep waters, unknown to all but a few. Both battled dragons and couatls, and in time, both saw the Elder Evils cast down and bound by the Silver Flame. After this defeat, the aboleths retreated to the depths where no dragon could follow them. In the hundreds of millennia since, they have slowly returned, spreading their influence across the world. Now the aboleths wait for the day when the Silver Flame will gutter and die, allowing the Elder Evils to return and claim the world as their own.
If you accept this version of Eberron's history, the aboleths become contemporaries of the Lords of Dust and enemies of the Chamber and the Church of the Silver Flame. The Elder Evils — those ancient powers bound by the Silver Flame — are also known as the rakshasa rajahs, though this latter name is simply a title. Eberron's history portrays these overlords as unique spirits with powers far beyond those of any rakshasa, and the Elder Evils detailed in Lords of Madness certainly fill the bill. Thus, they can also serve as the powers behind The Lords of Dust and the Carrion Tribes of the Demon Wastes.
Like the dragons and the rakshasas, the aboleths have the perspective required to study and understand the Draconic Prophecy fully, and they have discovered segments of it hidden in the deep waters. Like the rakshasas, the aboleths seek vengeance against the dragons and intend to twist the path of the Draconic Prophecy. As a result, characters working for the Chamber can easily be drawn into conflict with aboleths and their agents.
Size/Type: Huge Aberration (Aquatic, Psionic)
Hit Dice: 8d8+40 (76 hp)
Speed: 10 ft. (2 squares), swim 60 ft.
Armor Class: 16 (–2 size, +1 Dex, +7 natural), touch 9, flat-footed 15
Base Attack/Grapple: +6/+22
Attack: Tentacle +12 melee (1d6+8 plus slime)
Full Attack: 4 tentacles +12 melee (1d6+8 plus slime)
Space/Reach: 15 ft./10 ft.
Special Attacks: Psi-like abilities, slime
Special Qualities: Aquatic subtype, darkvision 60 ft., mucus cloud
Saves: Fort +7, Ref +3, Will +11
Abilities: Str 26, Dex 12, Con 20, Int 15, Wis 17, Cha 17
Skills: Concentration +16, Knowledge (any one) +13, Listen +16, Spot +16, Swim +8
Feats: Alertness, Combat Manifestation, Iron Will
Organization: Solitary, brood (2–4),or slaver brood (1d3+1 plus 7–12 skum)
Challenge Rating: 7
Treasure: Double standard
Alignment: Usually lawful evil
Advancement: 9–16 HD (Huge); 17–24 HD (Gargantuan)
Level Adjustment: —
The aboleth is a revolting fishlike amphibian found primarily in subterranean lakes and rivers. An aboleth has a pink belly. Four pulsating blueblack orifices line the bottom of its body and secrete gray slime that smells like rancid grease. It uses its tail for propulsion in the water and drags itself along with its tentacles on land. An aboleth weighs about 6,500 pounds.
Aboleths speak their own language, as well as Undercommon and Aquan.
An aboleth attacks by flailing with its long, slimy tentacles, though it prefers to fight from a distance using its illusion powers.
A psionic aboleth does not possess spell-like abilities or the enslave ability of the standard aboleth. Instead, it has psi-like abilities, including psionic domate.
Psi-Like Abilities: At will—disable (30-ft. cone, 12 HD, DC 20*), false sensor input (five targets, DC 16*), mental disruption (20-ft. radius, DC 18*), mindlink (unwilling, nine targets, DC 14*); 3/day—ego whip (ML 7th, 2d4, DC 17*), in insinuation (ML 7th, three targets, DC 17*), psionic domate (any target, 24 hours, DC 20*), thought shield (power resistance 21, 3 rounds*); 1/day—psionic modify memory (DC 17), remote viewing (DC 17), wall of ectoplasm (DC 17).
Manifester level 13th. The save DCs are Charisma-based.
*Includes augmentation for the aboleth’s manifester level.
Slime (Ex): A blow from an aboleth’s tentacle can cause a terrible affliction. A creature hit by a tentacle must succeed on a DC 19 Fortitude save or begin to transform over the next 1d4+1 minutes, the skin gradually becoming a clear, slimy membrane. An afflicted creature must remain moistened with cool, fresh water or take 1d12 points of damage every 10 minutes. The slime reduces the creature’s natural armor bonus by 1 (but never to less than 0). The save DC is Constitution-based.
A remove disease spell cast before the transformation is complete will restore an afflicted creature to normal. Afterward, however, only a heal or mass heal spell can reverse the affliction.
Mucus Cloud (Ex): An aboleth underwater surrounds itself with a viscous cloud of mucus roughly 1 foot thick. Any creature coming into contact with and inhaling this substance must succeed on a DC 19 Fortitude save or lose the ability to breathe air for the next 3 hours. An affected creature suffocates in 2d6 minutes if removed from the water. Renewed contact with the mucus cloud and failing another Fortitude save continues the effect for another 3 hours. The save DC is Constitution-based.
Skills: An aboleth has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.