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The Master Brain is found in a difficult to enter chamber in the Mind Flayers in Underdark - also known and marked as the Eastern Tunnels on the Underdark map.


This creature is an immobile and sedentary brain organism titled as "The Master Brain" in the game files. It is referred to as an "Elder Brain" in a few lines of text and dialogue. An Elder Brain is a type of illithid, as is an Alhoon or Ulitharid.

The brain has no physical attacks. It is also limited to only a couple of scripted actions. It can attack opponents in its detection range with Ego Whip, and it has a scripted ability to manifest actual Brain Golem allied guardians to defend against attackers within its chamber.

The Master Brain will create two Brain golems initially, and an additional single golem every 45 game seconds. This stops if the creature is destroyed.

Related Quests[]

The Drow Summoning Ritual - this quest will imply that a certain item, the Elder Brain Blood, is needed in order to fulfill a task for Matron Mother Ardulace Despana.


The creature's alignment was changed from Chaotic Evil to Lawful Evil in the Enhanced Edition.

Mod content[]

Mods icon This section is about unofficial content that is only available via fan-made mods.

The Sword Coast Stratagems mod revises the creature by changing the brain's class to mage and raising it to level 20. No other ability changes are made to its characteristics or abilities/immunities. In terms of the AI script however, SCS does make considerable modifications.

When a party member first enters the chamber, the combat screen will display:

"The reek of chemicals and fermented brain overwhelms you as you step into sight of the famed elder brain of the illithids. An instant later, the brain lashes out at you with a psionic whip...".

This attack will expose all party members to the Ego Whip affect, regardless of where they may be on the area map, even if currently undetected and elsewhere.

The brain is now scripted and able to apply the following Psionic Ability attacks at detected opponents: Psionic Disjunction, Psionic Domination, Psionic Maze, Detonate and Ballistic Attack.

The Master brain is able to recognize certain player protections from spells and specific equipped items which typically shield against psionic attacks. This creature can selectively attack with any of the provided psionic abilities or change to a less protected target if available. There is no single spell, innate ability, scroll, potion or item in the basic game which can protect against all of SCS's psionic abilities on their own.

The brain also summons the same Brain Golem allies as the unmodified game and will continue to summon one every 45 game seconds until it is destroyed.

The Golem Construction for Spellcasters mod adds a found item that can be recovered from the dead Master Brain - this item is called "Brain Tissue" which is a component for the party spell caster to create its own variety of Brain Golem to manufacture and have as a party-controlled allied creature.

External Links[]