Monarch, previously known as Captain Atom, spent sometime in The Bleed and madly believed that the Monitors are genocidal overlords who must be defeated; however, the Monitors assert that Monarch is a supervillain whose plan is to cause a Multiversal war that will leave him the ruler of the unified Earth remaining in its wake. In doing so, Monarch build up his army in the Bleed in order to be under the radar from the Monitors, in which he recruited Earth-3's Crime Society, Earth-10's JLAxis, Earth-8's Extremists, and among others. After the Monarch compiled a personal task force from his Arena battles, he opened his war on the exposed Monitors on Earth-51.
Throughout this world ending conflict, Monarch's army laid a overwhelming and devastating siege on Earth-51, killing its retired heroes and annihilating Earth-51's military resistance. Ultimately, Monarch's army came to an abrupt end when Superman-Prime inadvertently destroyed Earth-51 after tearing open Monarch's armor. So far, only the Extremists were known to have survived after teleporting back to their universe. And among others, the chances are very limited.
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