|Reactive Factory did not originate from fanon. This article can be edited freely by everyone in the community.
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Reactive Factory Zone is a racing course in the Sonic series. It started life as a racecourse in Sonic R; all the courses in this game were recycled for use in the Team Babylon storyline of Sonic Heroes 2 and to this day Reactive Factory remains the only entirely dedicated racecourse (over time, boundary lines for the zones have been reformed, leading to all the others being knocked into other zones) in existence.