User blog comment:Osain42/Wally West needs a new I.D/@comment-3094698-20120811195527/@comment-1038387-20120811200436

Dark Flash did exist. He was Walter West from an alternate future or alternate universe, the darkier and edgier version because the bad guys killed the wife.

Appeared in Flash v2 #152-159 and a few others comics. Don't know what happened to him, I think he went back to his own time.