Hunter was severely injured in an attack by Gorilla Grodd in Iron Heights, when Grodd staged a mass prison break, and was left paralyzed from the waist down. He asked Wally West to use the time-traveling cosmic treadmill in the Flash Museum to prevent this from occurring, but West refused, saying that he could not risk damaging the timestream. Zolomon, feeling that Wally should be prepared to disregard such fears for the sake of their friendship, then broke into the museum and attempted to use the treadmill himself. The resulting explosion destroyed the museum and shifted Hunter's connection to time - described by Jay Garrick as him being 'derailed' from the timeline by the explosion - thus allowing Zolomon to alter the speed at which he could move in time, giving him the effect of superspeed.
Zolomon decided that West had refused to help because, unlike the previous Flash Barry Allen, West had never suffered personal tragedy, and thus did not understand how terrible it could be. Zolomon decided that if he became the new Zoom and caused a great tragedy in Wally's life, this would help the Flash become a better hero