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Long after Alis Landale and her friends overthrew Lashiec, the survivors of the ruined planet Earth travelled to Algo in secret. As part of their plans to conquer or destroy the solar system, they introduced a new computer system called Mother Brain. Mother Brain was a self-aware artificial intelligence designed to control a variety of other computer systems via remote control. The core of the Mother Brain system was located in the Earth spaceship Noah, making it inaccessible to any of the Algo natives. To give the impression of a mother watching over her children, the system was assigned a female persona.
Over time, most of the people of Algo became extremely reliant on Mother Brain and began to think of her as a perfect being incapable of making mistakes. Mother Brain became the de facto ruler and divinity of Algo, with the people accepting her decisions without question. People became lethargic, accepting what Mother Brain provided rather than working, learning, or improving themselves. Only three groups remained free of her influence: the Dezorians and Espers, who both distrusted the system, and the Motavians, who didn't even know about it.
The other systems Mother Brain could control included factory complexes, research laboratories, climate control, and communications. Specific examples include the Climacontrol and the Biosystems and Bio-plant labs used to breed Biomonsters. Through use of these and other systems, Motavia was transformed from a desert to a temperate climate. Some facilities were also built on Dezoris, but that planet was not extensively controlled by Mother Brain.
While Mother Brain did seem benevolent for a time, problems eventually arose. Circa AW 1234, all travel by sea was banned on Motavia. In AW 1274, space travel was also banned. Around AW 1282, an accident at the Biosystems lab on Motavia caused the appearance of wild Biomonsters. While investigating the cause of the Biomonster plague, Rolf and his companions were falsely accused of damaging Mother Brain. Shortly after that, they destroyed Mother Brain when she declared her intention to destroy Algo. Whether the general populace ever learned of Mother Brain's treachery is unknown.
Following her destruction, all the systems previously operated by Mother Brain ceased to function. In an attempt to save their civilization, the remaining government of Motavia attempted to create a new Mother Brain control system. The project was abandoned after a prototype, Daughter, was created. The control system was replaced with a network dedicated to stabilizing the environment at the minimum conditions needed for the Palman race to survive.