Encounters: The Lowerdark (Underground, Wilderness)

Aboleth (CR 7)

Huge Aberration (Aquatic)
Alignment: Usually lawful evil
Initiative: +1 (Dex); Senses: darkvision 60 ft., Listen +16, and Spot +16
Languages: Aboleth, Undercommon, Aquan

AC: 16 (-2 size, +1 Dex, +7 natural), touch 9, flat-footed 15
Hit Dice: 8d8+40 (76 hp)
Fort +7, Ref +3, Will +11

Speed: 10 ft., swim 60 ft.
Space: 15 ft./10 ft.
Base Attack +6; Grapple +22
Attack: Tentacle +12 melee
Full Attack: 4 tentacles +12 melee
Damage: Tentacle 1d6+9 slime
Special Attacks: Enslave, psionics, slime

Abilities: Str 26, Dex 12, Con 20, Int 15, Wis 17, Cha 17
Special Qualities: Aquatic subtype, mucus cloud
Feats: Alertness; Combat Casting; Iron Will
Skills: Concentration +16, Knowledge (any one) +13, Listen +16, Spot +16, and Swim +8
Advancement: 9-16 HD (Huge); 17-24 HD (Gargantuan)

Climate/Terrain: Any underground
Organization: Solitary, brood (2-4), or slaver brood (1d3+1 plus 7-12 skum)
Treasure: Double standard

Source: Monster Manual

Transformation (Ex): A blow from an aboleth's tentacle can cause a terrible transformation. Affected creatures must succeed at a Fortitude save (DC 19) or begin to transform over the next 1d4+1 minutes, the skin gradually becoming a clear, slimy membrane. A transformed creature must remain moistened with cool, fresh water or suffer 1d12 points of damage every 10 minutes.

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 change.

Psionics (Sp): At will - hypnotic pattern, illusory wall, mirage arcana, persistent image, programmed image, project image, and veil. These effects are as the spells cast by a 16th-level sorcerer (save DCs, where applicable, are 13 + spell level).

Enslave (Su): Three times a day, an aboleth can attempt to enslave any one living creature within 30 feet. The target must succeed at a Will save (DC 17) or be affected as though by a dominate person spell cast by a 16th-level sorcerer. An enslaved creature obeys the aboleth's telepathic commands (but will not fight on its behalf) until freed by remove curse or dispel magic, and can attempt a new Will save every 24 hours to break free. The control is also broken if the aboleth dies or travels more than one mile from its slave.

Mucus Cloud (Ex): An aboleth underwater surrounds itself with viscous cloud of mucus roughly 1 foot thick. Any creature coming into contact with inhaling this substance must succeed at a Fortitude save (DC 19) or lose the ability to breathe air for the next 3 hours. The 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.

An aboleth attacks by flailing with its long, slimy tentacles, though it prefers to fight from a distance using its illusion powers.

Underdark Encounters