After discovering the Flash’s secret identity, Eobard traveled back in time to destroy Barry as a boy but was stopped when the Flash got his younger self to safety. An outraged Eobard then slew Nora Allen and framed Henry Allen for the offense instead. But later when he tried to travel back to his own future, Eobard lost his tie to aforementioned Speed Force, becoming stranded in the 21st century. By mimicking Dr. Harrison Wells, he formed a new life for himself as the leader of S.T.A.R. Labs and hastened through limitations holding back the making of a particle accelerator to ensure that Barry would grow into the Flash. Eobard would then show the Flash how to improve his rapidity so that Eobard could use the hero’s link to the Speed Force to return to his personal time. However Eobard had no reservations about killing several people to keep his and Barry’s secret safe, but their convenient “disappearances” carried the doubts of Joe West. After Joe convinced Barry that something wasn’t right with Eobard, he ultimately discovered the fact about Eobard’s identity. When Eobard sought to control Barry’s speed to retire to his own time by letting Barry plunge into his history, he instead foiled Eobard’s plot, then Eobard tried to kill him. But during this Eddie killed himself, causing Eobard to be deleted from existence. Its like he had a high pressure washer wiping him from the face of time.
Over one year later, a youthful Eobard was able to return as a time trace preserved by the Speed Force, working as reverse flash past before mimicking Wells, who meets The Flash for the first time. He also engages Cisco and sees his role in granting him his powers, learns about S.T.A.R. Labs and appears as the Earth-Two Wells, which would later help him to steal Earth One Wells’ impression in his future plan. Though after losing his dad, a guilt-ridden Barry wished to travel back in time and save his mother through beating Eobard out before he could murder Nora, dramatically altering all of history and Eobard’s future actions, cancelling his death in the future.