The Netherbrain

The Unbreakable Will of the Netherbrain
The Unbreakable Will of the Netherbrain
Huge Aberration
Level 20 Aberration
Stats
Hit points	300 (Balanced); 450 (Tactician);
Movement speed	0 m (0 ft)
Weight	10000 kg (20000 lb)
Initiative	-15
Ability scores
STR
STR	STR
Proficiency bonus	+4
Saving throws	Str +2; Dex 0; Con +10; Int +13; Wis +9; Cha +11;
Conditions
Chains of Karsus;	Will break free of its domination within 5 turns
Against All Odds;	Begins with a portion of its HP mission, depending on an earlier ability check
Aegis of the Absolute; Honour	Gains immunity to recent forms of damage
Features
Psionic Retribution;	Use a reaction to release a brainquake
Actions
Retributive Brainquake;	10d6Psychic and Mindbreak in response to damage.
Orb of Negation;	Mark platforms for negation, destroying them the next turn.

The Netherbrain
The Netherbrain
Level 20
Role	Overarching Antagonist
Voiced by	Cissy Jones, Various
Information
Title	The Absolute
Race	Elder Brain
Age	1000's of years

The Netherbrain is the final boss of Baldur's Gate 3. It is an Aberration.

“	Bhaal's Chosen placed the Crown upon me in the depths of Moonrise Towers, and there I was born.	„
	— The Netherbrain

Overview

Background

The Netherbrain is an empowered elder brain who was "enslaved" by the Dead Three, brought under their command by the Crown of Karsus. However, in truth, the brain was guiding events, amassing an army for itself and pitting the Chosen against each other, all the while empowered by the Crown.

Related quests

Confront the Elder Brain
- Destroy the Elder Brain
- Control the Elder Brain

History

The Netherbrain was created, unintentionally, by the Dark Urge, as part of a larger plan to create an army of illithids with the Crown of Karsus, controlled by proxy of a dominated elder brain wearing the Crown.

The Urge and Enver Gortash devised a plan to steal the Crown of Karsus from Mephistopheles' vault and use it to create a mind flayer army to exterminate all life as tribute to Bhaal. After successfully obtaining the Crown, it was brought to the elder brain located beneath Moonrise Towers, beginning the brain's time as the Absolute. ^[1] However, while at Moonrise Towers, the Urge was betrayed by Orin, who attacked them and took their place as Bhaal's chosen of the Dead Three.

Though the brain was inspired by the Urge's plan, happy to follow along and grant them their army, ^[2] without them, the Dead Three's plans quickly fell apart. With the Dark Urge out of the picture, the Dead Three squabbled and fought among themselves, with Ketheric^[3] and Orin planning to betray their fellow Chosen. Unimpressed, the Netherbrain began planning its takeover, giving power to each of the Chosen enough to harm the others.^[4]

While the brain could be controlled, so long as all three Netherstones were separate from the Crown, it was still able to guide events to its favour. The Netherbrain granted the Emperor its freedom so it could retrieve the Prism, and planted the knowledge of Orpheus' power. Unwittingly following a larger plan, the Emperor and his protected allowed it so that at least one Netherstone would be brought back to the brain, and it would be liberated.

Combat

Conditions

Chains of Karsus - After using Karsus' Compulsion on the Netherbrain
Against All Odds - If a natural 20 was rolled on the final check to dominate the Netherbrain at the Morphic Pool it will have this condition, which will greatly reduce its HP.
Aegis of the Absolute - On Honour mode only, the Netherbrain becomes immune to all types of damage that was dealt to it the previous round.

Attacks and abilities

Tactics

Accessing the Netherbrain

Dimension Door, Arcane Gate and Misty Step are all useful spells to have assigned or distributed as scrolls for moving from the entrance to "Atop the Netherbrain", over to the Crown of Karsus.
Stepping anywhere on the brainy surface will summon tentacles, so it may be easier to approach from the two platforms on either side. Otherwise, if intending to sprint across, using a character who can avoid Opportunity Attacks, such as one with the Mobile feat.
Globe of Invulnerability is also useful for protecting the caster of Karsus' Compulsion. However, the nearby Mind Flayers will still be able to stun creatures inside the globe, which ends the spell prematurely.
- Tossing Mind Flayers over the edge with moves like Telekinesis will not kill them, as they will just reappear atop the Netherbrain.
Only party members can enter the Netherbrain's Psyche (or The Unbreakable Will of the Netherbrain), so once the portal is open it is no longer necessary to continue fighting other enemies.

Fighting the Netherbrain

On Tactician, the Netherbrain will have 450 hit points.
The Netherbrain's hit point total can be reduced initially from rolling a natural 20 for the final skill check in the Morphic Pool
For each round, the first attack against the Brain will cause it to use Retributive Brainquake which will damage everything in range
The Brain will use Orb of Negation to summon several orbs which cause damage at the end of the next round. These orbs will destroy the platforms beneath them, so it is important to move characters off of any marked platforms. Further, the brain should be quickly killed before all platforms are destroyed.

Achievements

Hero of the Forgotten Realms
Save the day: kill the Netherbrain and destroy the Absolute tadpoles.

Absolute Power Corrupts
Reign with terror: take control of the Netherbrain and bend the world to your will.

Sins of the Father
Claim your Throne of Blood: take control of the Netherbrain for Bhaal and break the world.

Gallery

Concept art
Illusion
Crown of Karsus close-up
Cinematic
Load video
Local File
Local File might collect personal data.

Cinematic

References

↑ You brought the Crown to me, Bhaalspawn, thinking the army I amassed with it would become yours. - The Netherbrain to the Dark Urge
↑ Your plan was devious, your cruelty unparalleled. I would have followed it, were your mind not destroyed by your sister. - Netherbrain to the Urge
↑ Elder Brain Domination - Ketheric Thorm
↑ But with you gone, the three pitiful Chosen fought like children in your wake. I gave them power to harm one another with, while I crafted my design. - The Netherbrain to the Urge

External links

The Netherbrain on the Forgotten Realms Wiki

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[1] You brought the Crown to me, Bhaalspawn, thinking the army I amassed with it would become yours. - The Netherbrain to the Dark Urge

[2] Your plan was devious, your cruelty unparalleled. I would have followed it, were your mind not destroyed by your sister. - Netherbrain to the Urge

[3] Elder Brain Domination - Ketheric Thorm

[4] But with you gone, the three pitiful Chosen fought like children in your wake. I gave them power to harm one another with, while I crafted my design. - The Netherbrain to the Urge

[1]

[2]

[3]

[4]