I couldn't finish 'em. Looks like this's gonna get complicated.
The Mother Brain is an enemy from the Soul of Rebirth after story included in the newer versions of Final Fantasy II. It can use the Swap 4 spell to switch HP and MP with a party member. This is especially dangerous to the party, as Mother Brain's comparatively low maximum HP can be imposed on your party members; fortunately, its accuracy with this spell is poor. It is best to kill this enemy as quickly as possible.
The name of Mother Brain refers to a central CPU with a high degree of sentience, whose appearance is often manifested as a female figure appropriate to its title. Mother Brain originated as the primary antagonist of the Nintendo series Metroid, while later series like Phantasy Star and Chrono Trigger would have their own similar but relevant take on the character archetype.