Baldur’s Gate 3: How to solve the brain puzzle in the Necrotic Laboratory in BG3

A brain teaser if there ever was one.

The brain puzzle in the Necrotic Laboratory of Baldur's Gate 3
Screenshot by Dot Esports

In order to fulfill Act two of Baldur’s Gate 3, you need to find yourself in the grueling Mind Flayer sanctum under Moonrise Towers.

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The only way to reach the Mind Flayer sanctum is by completing the Manipulate the Mind puzzle within the Necrotic Laboratory. If you are following Ketheric Thorm you will have to best this puzzle.

Where is the Necrotic Library in Baldur’s Gate 3?

Access to the Necrotic Laboratory comes after the first part of the Ketheric Thorm battle located on the rooftop of the Moonrise Towers. It is an area with the giant Illithid and you find it after defeating enemies in a room with a large red death circle.

After the battle, head further into the room, bearing southeast, to find a separate space. Here, a cutscene will play after you touch a console in front of a giant, red hole with claws.

After the cutscene is over, your brain will be connected to the console, and different parts of your brain will be segmented into nerves and neurons. It’s your job to figure out how these nerves and neurons interact to solve this brain puzzle in BG3.

Solving the Manipulate the Mind puzzle in Baldur’s Gate 3

A map screenshot showing the location of the brain puzzle
The location of the brain puzzle in the Necrotic Laboratory. Screenshot by Dot Esports

At the start of the Manipulate the Mind puzzle, you need to click on different colored sections of the brain at the start of the puzzle, which are labeled Memory (green), Reason (purple), Emotion (yellow), and Speech (blue).

Tip: No skill check zone!

There are no skill checks when you are solving the puzzle so no need to waste spells or magic here!

Then, match whatever color you picked with the other colors to make a path of nerves and neurons to reach the identical-looking section of the brain at the end of the puzzle. To do this:

  1. Click on the section of the brain you want to connect.
  2. With it selected, follow the nerve (white line) out of the section and see what neuron (spheres on the lines) it leads to.
  3. Click the neuron that appears first in the path and follow it to the next neuron.
  4. Repeat this until you reach the corresponding section of the brain on the other side.

It can be a bit tricky, though, as some of the brain sections have nerves and neurons that intersect with one another.

Tip: A picture to make it easier.

To make it easier to visualize, take a look at our finished brain puzzle in the screenshot below.

A finished brain puzzle in the Necrotic Laboratory
What the completed brain puzzle looks like. Screenshot by Dot Esports

Steps to complete the Necrotic Laboratory brain puzzle

To finish the puzzle on PlayStation consoles, use L3 in order to move the camera and click on the nodes! Here is a breakdown of the general direction you want to go for each section below.

You can look at the finished puzzle above for reference.

  • Reason (Purple): Go to the right neuron and then keep going straight until you reach the end of the puzzle with the last neuron going to the left to connect to the other section of the brain.
  • Speech (Blue): Go straight and then make an immediate right and stay straight the rest of the way.
  • Memory (Green): Go down and then make a left to get to the puzzle’s centre. Go straight up and then straight again to reach the end.
  • Emotion (Yellow): Go straight to the center and then make an immediate hard left. Follow the line straight and your next moves will be back to the center and then straight.

With the Manipulate the Mind puzzle solved, you will be able to access a secret stone carving in the back of the laboratory that provides some insight into the mind flayers in Baldur’s Gate 3.

Author
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Joey Carr
Joey Carr is a full-time writer for multiple esports and gaming websites. He has 6+ years of experience covering esports and traditional sporting events, including DreamHack Atlanta, Call of Duty Championships 2017, and Super Bowl 53.