The Anti-Monitor is a fiction character, a comic book supervillain and the antagonist of the 1985 DC Comics miniseries Crisis on Infinite Earths. He first appeared in Crisis on Infinite Earths #2 (although he remained in shadow until Crisis on Infinite Earths #5), and was destroyed in Crisis on Infinite Earths #12, only to return after a long absence in Green Lantern: Sinestro Corps Special #1 (2007). In 2009, Anti-Monitor was ranked as IGN's 49th greatest Comic Book Villain of All Time.
The Anti-Monitor is not only an enemy of the Green Lantern Corps, but he is an enemy of the entire Multiverse. Billions of years ago, on the planet Maltus, there existed a race of beings, blue-skinned and immortal. One of these beings, Krona, was a scientist obsessed with the origins of the universe, even though a taboo existed amongst the ancient Oans concerning the viewing of the origins of the universe.
Krona created a machine that allowed him to see into the moment of creation. Somehow, his experiment disrupted the process of creation, with terrible consequences. The exact consequences have been rewritten over the years; originally, it was the unleashing of evil itself in the universe; later, it was assumed to be the creation of the evil antimatter universe of Qward.
During the Crisis on Infinite Earths, it was also revealed to be the cause of the existence of all parallel universes in the Multiverse; several villains were sent back in time to stop him, but were defeated by Krona and the other Oans. In a final revision, it was established that it increased entropy in the universe, shortening its existence by a billion years (see heat death). In any event, two beings were created on both the moon of Oa and the moon of Qward. On the moon of Oa, the being known as the Monitor was instantly aware of his counterpart, the Anti-Monitor (although his official name is the Monitor, and he is often addressed as such, the name Anti-Monitor is used to distinguish him from his heroic positive matter counterpart). By this time the Anti-Monitor had quickly conquered Qward, as well as the rest of the Antimatter universe. In searching for other places to conquer, he also became aware of his counterpart. These two beings battled for a million years, unleashing great powers against each other, but to no avail. At the end of their stalemate, they rendered each other inert for nine billion years with a simultaneous attack.
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Official Site: DC Comics
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