|Vehicles and/or Gadgets||None|
|Occupation|| Leader of Gremlins (2nd film)|
|Residence||Clamp Trade Centre and Retail Concourse|
The Brain Gremlin is the main antagonist in Gremlins 2: The New Batch, the secondary antagonist being Mohawk. He is a brown mutated gremlin who wears glasses and later on more formal clothing. He has a well-spoken human voice which he got after consuming a beaker full of mutagenetic brain hormone serum in the Clamp Center laboratory, which also had the effect of greatly increasing his intelligence. Afterwards, he dressed more like a human, wearing very business-like clothing and even gaining spectacles that had appeared from no known location or source. Although he is a villain, he is very articulate and cultured for a gremlin, though his mischievous nature still prevails. He does not appear to be as destructive as the other gremlins and appears to be somewhat fascinated by the humans' culture and way of life.
- In Gremlins 2: The New Batch, he was voiced by the late Tony Randall. In LEGO Dimensions, he is voiced by Christopher Swindle. Swindle also voices Betelgeuse in the game.