Black Flash

The Black Flash is a DC villain who is actually one of the many embodiments of Death itself - though Black Flash only goes after the souls of people who possess superhuman-speed connected to a special power known as the Speed Force.

It's unclear why Death takes on the form of Black Flash to track down speedsters - though some theories are made that either top-rate speedsters (such as the Flash) are too fast for traditional Death to catch up with or that Black Flash is a result of some kind of anomaly caused by the Speed Force itself, whatever the cause Black Flash exists for one purpose: to end the lives of speedy heroes and villains in the DC universe.

It should come as no surprise that the Black Flash is an enemy of the Flash (both past and future-versions) but his appearances are fairly rare - as is the case for most personifications of death, after all the arrival of the Black Flash usually suggests that Flash is about to die or in serious danger of doing so.. though unlike most versions of Death the Black Flash is capable of being defeated or at least stalled so not all encounters with the entity need be fatal to a speedster, though a victory against a being like Black Flash is likely in vain as he will keep coming back until his job is done..