We first met the Reverse-Flash a few issues back, discovering just who he was and how dangerous he is. What we haven't discovered is what, precisely, is driving him to kill users of the Speed Force. Until now, that is, with the one-shot for Villains Month focusing on Reverse-Flash.
Francis Manapul and Brian Buccellato have been having a truly great run on The Flash, and the Reverse-Flash has been a villain they've had some clever ideas for. Buccellato actually had one of the best one-shots last week with his take on Grodd, and this one promises to be just as good with his coplotter at the helm and Scott Hepburn serving as guest artist.
Specifically we get to dig into the mind of Daniel West a little bit. West is Iris' sister and not exactly Barry's biggest fan, and he blames his father for, apparently, driving him away from his sister. That's why he's killing Speed Force users; the more power he has, the further he can go back in time, to the point where, supposedly, his father destroyed their family even more than he already has.
Of course, you can't blame him for wanting to give his old man some pain back, as we see in this preview...