In Batman: The Merciless #1, out last week from DC, writer Peter J. Tomasi and artist Francis Manapul brought fans the story of one of the Dark Knights -- Batmen from the Dark Multiverse. This one? The one who was...ahem...inspired by the death of Wonder Woman.
The issue opens with Superman cradling the corpse of Wonder Woman on Earth -12, and fulfills the promise of explaining how Wonder Woman's death transformed him into The Merciless, a character who wears a Batman-inspired version fo Ares's armor and harnesses the powers of the old gods.
Here, Batman as Ares takes a different view of his "war on crime" than he does as the Dark Knight, using the God of War's abilities to eradicate threats. For much of the issue, which takes place during the Dark Nights: Metal event, the Merciless launches an attack on ARGUS, monologuing to themselves about how they do not understand war the way he does.
He remembers swearing vengeance on Ares after Wonder Woman seemingly died at the god's hands. He fulfills that promise, taking on the role of Ares and taking over his world.
In the end, he is about to murder Steve Trevor -- who was attempting to stop him. The helmet of Ares, he explained, drove him and made him inhuman, cruel, and powered by death and war. In an interior monologue, he apologizes to Wonder Woman -- not for potentially killing her Earth-0 love interest, but for murdering her on Earth -12 when she turned out not to have died at Ares' hand and reached for the helmet.
This week sees the release of Batman: The Devastator, which details a version of the Dark Knight who injected himself with the Doomsday virus in order to defend his universe from Superman-level threats.