How to Complete Necrotic Laboratory Puzzle in Baldur’s Gate 3

The Brain Connection puzzle appears in the Necrotic Laboratory in Baldur's Gate 3, and this guide shows you how to complete it.

In the climax of Baldur’s Gate 3 Act 2, you’ll explore the Illithid Colony growing underneath Moonrise Tower. This colony has been where all of the tadpoles have been coming from and where much of the region’s power is held as the Absolutes make their move for power.

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While all of this is going on, there’s a chance you might encounter a Brain Connect puzzle in the Necrotic Laboratory. There’s a terminal that reaches out to your character’s brain, and you’ll have to connect one half of the brain to the other side. Here’s what you need to know about how to complete the Brain Connect Puzzle in the Necrotic Laboratory in Baldur’s Gate 3.

All Necrotic Laboratory Puzzle Solutions in BG3

Screenshot by Gamepur

The Necrotic Laboratory Puzzle will be on a side path as you make your way through the Illithid Colony. This area only becomes available at the end of Act 2, when you’re about to face off against Ketheric Thorm, and he’s taken the Nightsong if you saved her before entering this part of Baldur’s Gate 3. You’ll find a terminal in the Necrotic Laborartory that you can interact with, and then you’ll see that the brain needs to be finished and put together manually.

You need to complete four sections for this Baldur’s Gate 3 puzzle: Reason, Memory, Emotion, and Speech. You do not need to complete these puzzles in any particular order, but this is how I worked through them for my Baldur’s Gate 3 playthrough.

Screenshot by Gamepur

First, I went through Reason, carved through the upper part of the connections, and finished that up. This only took five nodes to complete.

Screenshot by Gamepur

Next, I worked on Memory, which took me through the lower part of the puzzle and then up to the upper layer. I needed only to connect four nodes to complete this route to solve the Necrotic Laboratory Puzzle in BG3.

Screenshot by Gamepur

Next, I began running through the Emotion portion of the Braind Puzzle. This was a bit more complicated but was not too challenging. This one also only required four nodes to connect to the final one.

Screenshot by Gamepur

Finally, I worked through the final part and the Speech portion. This was the last part of the Necrotic Laboratory Puzzle in this part of Baldur’s Gate 3. When I finished this puzzle, it opened up the area in the back and learned a small lore tidbit about this Illithid Colony. It is important to note that not all of the nodes are used, so you don’t need to fill out the entire brain puzzle to complete it.

Although this is a minor side activity in Baldur’s Gate 3, this might provide a bit more background regarding the push by the Illithids and the Absolute. Despite being a Cult, their overall goal is to achieve the Grand Design, where the Illithid wants to see everyone in the world become like them.


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Author
Cande Maldonado
Though Cande started her journey in the video game industry as a localization specialist six years ago, she soon realized that her true calling was to annoy NPCS, smash virtual pottery, and complete every side quest available in RPGs. Throwing that useless degree out of the window, she has been writing professionally for the past three years ever since. Her passion for games dates to 2006, when she mounted a Chocobo for the first time. Under Nintendo and Square Enix's chokehold, she will willingly pour hours upon hours into reaching 100% completion in the longest roleplaying games ever made. But hey, who needs fresh air and sunlight when you can just live in Ivalice?
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Zack Palm
Zack Palm is the Senior Writer of Gamepur and has spent over five years covering video games, and earned a Bachelor's degree in Economics from Oregon State University. He spends his free time biking, running tabletop campaigns, and listening to heavy metal. His primary game beats are Pokémon Go, Destiny 2, Final Fantasy XIV, and any newly released title, and he finds it difficult to pull away from any Star Wars game.