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Intro. The "Victory Virus" Failed Given that the Umamusume are beings with superior physical capabilities (capable of running at more than 60 km/h), a probable origin would be a scientific experiment to enhance their performance. The Experiment: A laboratory seeks to synthesize the "essence" of the Three Goddesses (the progenitors of the Umamusume) to create an ultimate energy supplement. The Mistake: The compound mutates into a pathogen that, instead of empowering the body, keeps it in a state of permanent "running frenzy". Patient Zero: A runner at Tracen Academy consumes the supplement before a workout. When she collapses, the virus reanimates her nervous system, turning her into a being driven solely by the instinct to "hunt" and run.

Umamusume Zombie AU

@Harmonia