From Final Fantasy Wiki
The Twin Brain is an enemy from Final Fantasy VII. Due to the Twin Brain's heavy amount of Magic Defense they will probably resist most low level spells thrown at them, and with their Stare Down technique that causes paralysis, it might put you in a very difficult position in battle. The Twin Brain is the source of Turbo Ethers early in the game (if you happen to have Morph available) and a ready supplier of Ethers for stealing, so the struggle to defeat these tough enemies is worthwhile.
[edit] Related enemies