Baldur’s Gate 3 Necrotic Laboratory Puzzle Solution

Underneath the Moonrise Towers there is a Necrotic Laboratory Puzzle linked with the Ketheric Thorm quest in Baldur's Gate 3. Although it is not necessary to complete, you can get some very nice items if you do.

You will encounter the mind link puzzle inside the Necrotic Laboratory during Act 2 of Baldur’s Gate 3 after your first battle with Ketheric Thorm. This puzzle involves linking several color-coded nods, which, when you complete it, opens the Flesh-Wrought door in the area. 

The Necrotic Laboratory can be found inside the mind-flayer colony underneath the Moonrise Tower. Once you defeat Ketheric Thorm, he escapes into the Mind-Flayer colony through the Oubliette. Follow him there, and simply following the path will get you to the location of the puzzle.

How to solve Necrotic Laboratory puzzle in Baldur’s Gate 3

The mind link puzzle is not that difficult, and all it needs is for you to pay close attention to the symbols and nodes. There are four pieces of brain, each colored differently to represent a specific feature. The purple brain represents reason, the green one represents the memory, the yellow brain is emotion, and the blue brain represents speech. 

The purpose of this puzzle is to connect each kind of brain to its counterpart on the other side of the neural network. If you rotate the camera and move it up and down, you will notice layers of nodes.

Purple Brain

For the Purple Brain, link all the nodes at the top of the 3D structure. Manipulate the neural path until you can see the top nodes clearly, as it can be difficult to make it out without scrutinizing it. Follow the picture below to complete the first portion of this puzzle.

Yellow Brain

For the Yellow Brain, connect to the node right in front of the brain, then to the one directly to the left, and continue straight onto the next. Lastly, connect to the immediate node on the left and then to the final one on its immediate left. The picture below will give you a better understanding.

Blue Brain

For the Blue Brain, just keep going straight until you reach the other blue brain at the end of the neural network. It can be best explained with the picture above.

Green Brain

For the Green Brain, first, connect the initial node to the bottom node, then connect it to the one right in front of it (towards the north). Next, go further north and connect it to the highest point right in front of the previous node, then finally connect the nodes to the two nodes on the left. The picture below will give you a better understanding.

Necrotic Laboratory Puzzle Rewards

Completing the Necrotic Laboratory Puzzle in BG3 opens the Flesh-Wrought door right before you. You can then continue with the Ketheric Thorm quest. Within the room, you also receive three rewards. These rewards include the likes of the Blade of Oppressed Souls, the Braindrain Gloves, and the Circlet of Mental Anguish. 

Reward Attributes 
Blade of Oppressed Souls (+1 Longsword) 1D10 (Slash Damage), 1D4 (Psychic Damage) 
Braindrain Gloves Causes fatigue in enemies for two rounds if you inflict psychic damage 
Circlet of Mental Anguish Recovers HP when the enemy fails a saving throw against your spells. 
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