The Black Flash is a fictional comic book character from DC Comics. Created by writers Grant Morrison and Mark Millar, and artist Ron Wagner, the character first appeared in Flash (vol. 2) # 138 (June 1998).
The Black Flash essentially fulfills the same role as Death for those who possess super-speed in the DC Universe, returning them to the source of their powers: the Speed Force. It is reportedly seen before the deaths of Barry Allen and Johnny Quick; Max Mercury, having had several near-death experiences, has also seen the Black Flash.
It is not clear whether the Black Flash exists because the speedster characters are simply too fast for traditional Death to capture, or as some sort of bizarre side-effect to their connection to the Speed Force.
It came for Wally West to draw him back to the Speed Force, but instead took Linda, Wally's girlfriend; having seen portents of Wally's death, Max Mercury and Jesse Quick intercepted him before he could reach the museum where Linda was waiting for him, with Linda thus being struck by the lightning that was meant to kill Wally. It later returns to try to take Wally again, freezing time except for those who possess a connection to the Speed Force. Max Mercury, Jay Garrick, and Jesse Quick all attempt to assist Wally by distracting the Black Flash; Wally finally defeats the Black Flash by racing it to the end of time, to a point where Death would have no meaning, causing it to dissipate.
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