Waking Mind

The Waking Mind is a unique item found in the Mind Flayer Colony in Act Two.

A humanoid brain - alive and in perfect condition - suspended in cerebrospinal fluid.

Properties

In the Necrotic Laboratory inside the Mind Flayer Colony after solving the brain mapping puzzle

Speaking to the head can grant the permanent buff  Githzerai Mind Barrier. The player character must choose either Illithid Persuasion dialogue option (consume / purge her mind) to receive this buff.
When placed on the Mind-Archive Interface within the Mind Flayer Colony, the  Slack-Skinned Head speaks:

HmmMM... fine bones... sharp jaw... some variety of elf?
Pretty enough for a flesh-prison - if not the noble githzerai features I was born with.
I'd guess you're no willing guest of the ghaik either. Perhaps we might aid one another.

 History Check: *The monk-like githzerai, sibling-race to the warrior githyanki. Their contempt for one another is eclipsed only by their shared hatred of the illithids.*
Reply: How did you end up in that vault? Githzerai are supposed to be ultimate warriors.

Warriors of the mind. Oh, there's some physical prowess involved, but the battlefield on which we truly fight the ghaik is their own.

Well, a githyanki skull would be too tight a fit, cousin. Your people shunned psionics, after all - while mine mastered them.

Reply: [GITHYANKI] How did you end up in that vault? Aren't you zerai ultimate warriors?

Warriors of the mind, cousin. A discipline unknown to your kind - and the very reason we were attacked.

Oh, for a set of hands to slap your face. The yanki lost their way the moment Gith threw down the Ghaik empire.
Only we zerai continue the war to end the ghaik forever. Only we fight them on their own battlefield - the mind.

A githzerai's mind is not so easily cracked. Our discipline was the very reason we were attacked.

Reply: I'm listening. What aid are you offering?
My order taught a psionic technique much-feared by the ghaik. They destroyed us for it, and kept me as a trophy.
I never broke, but... I've spent all these centuries awake. Aware. So here is my offer:
Use your tadpole. Erase me - and I will pass my technique onto you.

 Warlocks feel the monk's lie without a check with the help of their patron: *A prickling flame runs across the back of your mind and the edge of your soul.^[1] Your patron bids you caution before agreeing to this pact. The monk isn't telling you everything.*
Reply: If you want my help, then tell me the truth.

...All right. I... the ghaik did not find my monastery. I led them there.
They promised me immortality. And they gave it - I have been their rotting trophy for centuries.
*As her agitation swells, so does her latent psionic power. To your tadpole, that guilt and terror are almost... fragrant.*
*You realise the illithids locked her away not as a trophy, but as a fine vintage.*
Please - touch my mind, and purge it. The moment you do, my knowledge will be yours.

My people dwell in Limbo - a realm of pure, chaotic thought. With my mind gone, perhaps my soul will return there.
Or perhaps not. Death, freedom - they are one and the same.

Reply: I'll do it.
Touch my mind, and purge it - at the very moment you do, I will make my knowledge yours.

Reply: When you say 'erase' your mind - do you by any chance mean 'smash your brain to bits'?

...I do not. The ghaik have been warping flesh for millennia - who knows what damage they can undo.
It is my mind they enslave. It is my mind that must die.

*The awareness that floods you is nothing like the tadpole. It is tentative, and tingled with the loneliness of aeons.*
*It fades beneath your touch, but you feel something left behind. A fragment.*
It's only knowledge yet, without comprehension. But when you use it, you will... see...
And I... I see...