Story: A speedster created by the dark matter release of the Particle Accelerator in Earth 2, Zoom became a villain with dark motivations. read more
Black Flash, as far as we know in the TV shows, can't be killed. It embodies death itself for speedsters and I really don't think it can die. Reverse Flash is Eobard Thawne, a speedster who can take advantage of the speed force. read more