Brain in a Jar

Type	Pet summon
Use time	20 (Very fast)
Tooltip	Summons a spider brain; 'Pickled and shrunken, this brain can no longer hurt you.'
Rarity
Sell	5
Research	1 required
Buff	Spider Brain
Buff tooltip	It's crawling around . . . icky
Use	https://terraria.gamepedia.com/File:Item_2.wav

Master Mode-Only Content: This information applies only to Master Mode and Master Mode worlds.

The Brain in a Jar is a pet item that can be dropped by Brain of Cthulhu in Master Mode with a 25*1/4 (25%) chance. It summons a miniature version of the Brain of Cthulhu, the Spider Brain.

Trivia[edit | edit source]

The Spider Brain slightly resembles the Brain Suckler, which latches onto human heads.
- Likewise, this pet and the object used to summon it may be a reference to a scene from the movie "The Iron Giant," where the main character is watching a horror movie in which a scientist knocks over a brain in a jar. Upon returning to his lab, the brain is no longer on the floor - two seconds later, the brain, now having developed four legs, two eyes and a mouth, leaps onto the scientists face.
- That being said, it is also possible, but less likely, that this item is intended as a reference to the arachnotron from the DOOM franchise.
The item itself may be a reference to the brain in a vat, a scenario in thought experiments which involves placing a disembodied brain in a vat of life-sustaining liquid and connecting it to a supercomputer, allowing the brain to perceive itself to be experiencing reality as if it were in the outside world.