Flash, Vol. 2

After using Captain Cold and Mirror Master to exile the Flash to one of McCulloch's mirror-worlds, Brother Grimm stole Keystone City and everyone in it. He encountered the Flashes when they helped to end his father's brutal reign, and Wally made a strong impression on him, encouraging him to follow his own path.

But seeing the atrocities his brother committed as king, Grimm took the throne back. And now, seeing Wally has taken up Barry's mantle as the Flash, he feels betrayed by him. And he's determined to take the things that are precious to him.