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As the ecological conditions on Motavia continued to deteriorate after the destruction of Mother Brain, the Artificial Intelligence systems responsible for maintaining the world determined that humans needed an edge if they were to continue to survive on the harsh world. To this end, the project that created Neifirst and Nei was revived. Rika is the final result of the revived project.
For the first year of her life, Rika lived the Bio-plant facility located in Zema's Birth Valley. She was trained and taught by Seed, the controlling A.I. of the facility, and Wren. Rika left the Bio-plant following the arrival of Alys Brangwin and her comrades. She continued to travel with this group as one of the four core members, growing close to Chaz Ashley and eventually entering into a romantic relationship with him.
During her travels, Rika displayed a heightened sensitivity to evil magic, particularly the Black Energy Wave. This trait, shared with Rune Walsh, allowed her to sense the locations of Dark Force entities.