The Reverse-Flash and the Flash battled each other for many years, with neither of them ever prevailing. Eobard eventually learns of the Flash's secret identity – Barry Allen – and travels back in time to the year 2000 to kill Barry as a child. He then encounters a version of Barry from the year 2023 who warns him of the potential consequences of his actions, but Eobard refuses to listen and continues his attempt to kill Barry's younger self. When his plan fails due to Barry's interference, Eobard kills Nora Allen and frames Henry Allen instead, hoping that a personal tragedy will prevent the Flash existing. In doing so, Eobard inadvertently severs his own connection to the Negative Speed Force and strands himself in the 21st century.