The origins of the Brain Monster are unknown, and it is a resident of the planet Autan. A massive brain needing to eat gold, it somehow forced the local Autanians to mine for the material it needed to eat. It also developed an army of Cube Men, robots that were an extension of its own powerful mind. By 1949, the Autanians, led by a man named Grail, revolted against the Brain Monster and refused to mine for gold. The Brain Monster then sent its Cube Men to Earth to collect gold from that planet. There the Cube Men brought back Sun Girl to present to their master because locals referred to her as the "Golden Goddess".
The Brain Monster told Sun Girl that it intended to eliminate the Autanians and harvest gold from Earth instead, but Sun Girl convinced the creature to let her talk to Grail and his people. Sun Girl has convinced Grail to feign subservience to the Brain Monster, and when the creature was distracted Sun Girl loosened her bonds and fired her sun beam directly into the Brain Monster's massive brain. The effect killed the Brain Monster and deactivated its Cube Men, ending the creatures threat.
Powers and Abilities
Technopathy: The Brain Monster has a powerful intellect that allow it to transmit its will into machines, in particular his Cube Men. The monster did not appear to have any other extra-cognitive abilities.
The Brain Monster was mostly immobile making it an easy target. It also relied on gold as its only form of sustenance.
The Monster Brain used tiny mechanical arms for limited function.