Devastator was created by Scott Snyder and Greg Capullo. He made his first appearance in Dark Days: The Casting #1.
Bruce Wayne is the Batman of Earth-1. His world's Superman went rogue, killing everyone on his path, regardless of whether the person is good/bad. Batman is the only person left, as he's about to strike his final blow, Batman tells him that he won't allow Superman to hurt him anymore. He injects himself with the Doomsday Virus. Batman has now become the monster and immediately starts pounding Clark, murdering him within a few minutes. He has now become the Devastator.
Powers and Abilities
Bone Protrusions - Like Doomsday, Devastator has many bone protrusions that are sharp and strong enough to pierce people as strong as kryptonians.
Doomsday Virus - Bruce Wayne injected himself with a modified version of the Doomsday virus and gained the ability to emit this virus turning others into Doomsday clones.
Genius Level Intellect
Super Speed - Comparable to Superman's combat speed.
Super Strength - Able to trade blows with the likes of Superman and Lobo with ease.