The Infusion recipe for the Brain in a Jar, as shown in the Thaumonomicon.

Brain in a Jar is a research option found under the Artifice tab that becomes available for research after researching Infusion and scanning a Zombie Brain, along with being an block. When placed down, the Brain in Jar will draw any experience orbs dropped towards it, storing them. The storage is limited to 2,000 experience, however, this is still potentially several levels worth of experience. This makes them useful for storing experience so that one, even after dying, can still enchant or perform other actions requiring experience. When the Jar has reached its limit of 2,000 experience, a particle effect, as shown below, will be emitted from the top of the Jar. The Brain in a Jar can be created by Infusing a Warded Jar with a Zombie Brain, 2 spider eyes and a bucket of water, the bucket is not used, however, along with 20 Exanimis and 10 Cognito and Sensus Essentia. It is classified as having Moderate Instability. Another interesting feature of the Brain in a Jar, however, is that the Brain itself will follow the player as they move around it, starting at 5 blocks away from itself, excluding the block it is placed in.

The particle effect emitted by a full Brain in a Jar.

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