<P> Blaming the Flash for his defeat, Thawne became obsessed with "replacing" Barry Allen and began traveling back in time to exact his revenge, using his knowledge of history to his advantage . When Barry's wife, Iris West, rejected Thawne's romantic pursuits, the latter apparently killed her by vibrating his hand through her skull . Shortly after Barry had found love again, Thawne returned and threatened to kill Allen's new fiancée, Fiona Webb, on their wedding day . Fearful that history was repeating itself, Allen inadvertently killed Thawne by breaking his neck . </P> <P> In a post-Crisis extended origin, the storyline "The Return of Barry Allen" in The Flash #74 - 79 revealed that Eobard Thawne was once a scientist from the 25th Century who was obsessed with the Flash, even undergoing cosmetic surgery to resemble Barry Allen . After obtaining the Cosmic Treadmill from an antique shop, Thawne gained all of the Flash's powers after replicating the electrochemical accident that created the hero, seeking to use the Treadmill to travel back in time and meet his idol . But due to a malfunction, Thawne arrived at the Flash Museum several years after Barry's death, where he discovered that he was destined to become "Professor Zoom", the "Reverse - Flash", and die at the hands of his idol . As a result, the unstable Thawne convinced himself that he was Barry Allen, and subsequently attacked Central City for "forgetting him". The current Flash, Wally West, ultimately tricked Thawne into returning to the 25th century with no memory of the incident . Despite this, Thawne still managed to bring the remains of his older self's costume with him, cluing him further into his destiny . </P> <P> After the events of Zero Hour: Crisis in Time, it is revealed that Eobard's ancestor, Malcolm Thawne, was Barry Allen's long - lost twin brother, meaning that Barry is Eobard's great uncle . </P> <P> In 2009, Eobard Thawne was re-imagined as a major villain in the DC Universe by writer Geoff Johns in The Flash: Rebirth . His resurrection is foreshadowed to occur in a near - future event, after which he would be responsible for Barry Allen's return and transformation into the Black Flash . It is later revealed that because Thawne recreated the accident that gave Barry his powers, he was able to lure Barry out of the Speed Force during the Final Crisis and temporarily turn him into the Black Flash . </P>

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