The Dark Multiverse is full of evil Batmen, but he’s not the only one-time hero to embrace the darkness. As the very first page of the issue blatantly shows, the Man of Steel himself has also gone to the dark side on the world of Earth -1. Unlike the Dark Knight, though, no reason or motivation is provided for Superman’s fall from grace –- even The Devastator’s narration shows that the circumstances for his turn are unknown. Instead, Superman’s mysterious transformation from hero to villain is merely used as the seed for Batman’s own transformation, and the reason for this world’s breakdown of its World’s Finest duo, presuming that the two were ever crime fighting partners in this reality in the first place.
It’s Batman v Superman, both literally and in terms of elements that evoke last year’s film of the same name. A seemingly-heroic Batman attempts, and fails, to take down the rogue Superman -– that is, until he unveils his own ultimate alteration into a Doomsday-like creature, a transformation that he can undergo back and forth at will. Upon unleashing the creature within, Batman, now The Devastator, delivers a gruesome and fatal blow to the Man of Steel in fairly short order. As has happened in each of the Dark Knights’ origins to date, the Batman Who Laughs arrives at this crucial moment, enlisting The Devastator in his eventual assault on Earth-0.
Upon arriving on Earth-0, The Devastator, perhaps appropriately, makes his way to Metropolis, where (as Bruce) he visits Lois Lane at the Daily Planet, before changing back to his Devastator guise and seemingly infecting Lois with the Doomsday virus. Although citing her as the virus’ source, it’s his arrival that appears to have contaminated the city, as its citizens have already begun their own hideous transformations. Her own conversion, however, is slow in coming, which Devastator credits to her constant proximity around Superman. Metropolis’ extended Super-family –- Supergirl, Guardian, and Superwoman -– subsequently show up to confront The Devastator, but Kara (and presumably the others) also seem to succumb to the virus.
Infecting Earth-0 with the various ills unique to the Dark Knights has shown to be an instrumental part of Barbatos’ plan. As the Doomsday virus begins to infect the entire city of Metropolis, so has Bryce Wayne’s Dead Water “virus,” which created her own army and later infected Mera, as seen in Batman: The Drowned. The Murder Machine’s cyber-virus has been seen creating havoc in Detroit, and The Red Death has inflicted a form of decay across Central City. With the darkness of the Dark Multiverse literally infecting Earth-0, a Joker venom-type contagion seems to be a logical upcoming fate for Gotham, based on the tendencies of some of the other Dark Knights.

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