Mother Brain is the primary antagonist of Super Star Soldier and the parody game Star Parodier. After the Star Brain Corps' defeat in the original game, four years later, they return under the command of the Mother Brain to take over Earth. As a result, Earth sends in the Neo Caesar to do battle against the Star Brain Corps once again.
Mother Brain will alternate between a barrage of lasers, firing from its frontal cannon and launching a barrage of destructible rings. Once the frontal cannon is destroyed the brain will become vulnerable, so it will begin shooting lightning bolts aimed at the player which are difficult to dodge.
Once it takes enough damage the brain will ditch its robotic body and start floating around, shooting various rings at the player while being surrounded by more brains, which will sometimes break out from the central brain and attack individually.