Anti-Matter Man

"There is no planet Earth in the antiverse, but there is a world called Qward. Qward is a place of pure malevolence, and Anti-Matter Man is a walking living expression of evil. He is more than a hundred meters tall, and beyond the considerable powers he possesses, in a positive matter universe his mere touch bring explosive decay and death. The Weaponers of Qward created Anti-Matter Man as a weapon, to be used in an invasion of the positive matter universes. But so great and terrible was his power that even the Weaponers feared him. And so they locked away their creation, sealing him within the core of a moon."

- The Stranger about the Anti-Matter Man's origin to Barry Allen

The Anti-Matter Man is a weapon originated from Qward in the antiverse whose goal is to invade the positive matter universes. In an alternate timeline, it caused a crisis in 2018.

Creation
At some point, the Weaponers of Qward created the Anti-Matter Man as a weapon to invade the positive matter universes but due to the dangerously of the weapon, the Weaponers sealed it within the core of a moon.

Crisis of 2018

 * The following took place in an alternate timeline where Flashpoint never occurred.

At some point, the Anti-Matter Man escaped his confinement and started to target the positive matter universes. In 2018, the Anti-Matter Man arrived on Earth-27 and his presence stated to poison the atmosphere killing all of its resident except a few thousand of speedster in Central City and the Crime Syndicate of America who has succeeded in passing through a breach. After destroying Earth-27, the Anti-Matter Man tried to reach the breach to Earth-1 but due to his low speed, he failed to reach the breach before the heroes of this universe close it.

Powers

 * Positive matter's destruction: The touch of Anti-Matter Man with any positive matter cause the positive matter to be destroyed to the point that a universe's atmosphere could become poisonous.

Weaknesses

 * Slowness: Despite being big and powerful the Anti-Matter Man is incredibly slow to the point it will take hours to reach a breach.

Behind the scenes

 * In the Dc Comic, Anti-Matter Man is a cosmic being from the Antimatter universe that came face to face with the Justice League and the Justice Society.