monster

Infected Elder Brain

CR 11

Large Aberration (mind flayer), Lawful Evil

Reveal Stat Block

Armor Class

Hit Points

189 (18d10 + 90)

Speed

5 ft., swim 10 ft.

str

dex

con

int

wis

cha

Traits

Creature Sense.The elder brain is aware of creatures within 1 mile of itself that have an Intelligence score of 4 or higher. It knows the distance and direction to each creature, as well as each one's Intelligence score, but can't sense anything else about it. A creature protected by a mind blank spell, a nondetection spell, or similar magic can't be perceived in this manner.

Magic Resistance.The elder brain has advantage on saving throws against spells and other magical effects.

Telepathic Hub.The elder brain can use its telepathy to initiate and maintain telepathic conversations with up to ten creatures at a time. The elder brain can let those creatures telepathically hear each other while connected in this way.

Actions

Multiattack.The elder brain makes two Tentacle attacks.

Tentacle.mw 6 to hit, reach 30 ft., one target. ({@damage 3d8 + 2) bludgeoning damage. If the target is a Huge or smaller creature, it has the grappled condition (escape 14) and takes 9 (1d8 + 5) psychic damage at the start of each of its turns until the grapple ends. The elder brain can have up to four targets grappled at a time.

Mind Blast 5.Creatures of the elder brain's choice within 60 feet of itself must succeed on a 17 Intelligence saving throw or take 32 (5d10 + 5) psychic damage and have the stunned condition for 1 minute. A stunned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Infected Elder Brain

The Far Realm has tainted the elder brain that fuels Illithinoch's mind flayers.