Mobius (Antimatter Universe)

Mobius is a being from the Antimatter Universe that destroyed the Original Multiverse.

Early life
At the dawn of time, his doppelgänger Mar Novu accidentally traveled to his universe causing him to discover the existence of the multiverse. At some point, after Mobius gave himself the objective to destroy the multiverse, he was confined by Mar Novu in order to protect the multiverse in time to recruit heroes.

Capturing Barry Allen
In 2018, the Flash from Earth-90 was transported to his universe by Mar Novu. Mobius would capture him and trap him on a treadmill in order to power his anti-matter cannon.

Released from his confinement
On December 9, 2019, Nash Wells who managed to find his confinement tried to force it in order to kill him believing him to be Mar Novu. Nash was arguing with Mobius until he was attacked by one of Bloodwork Blood Brother. After that Nash has successfully survived the Blood brothers attack, believing that it was Mobius who saved him, he opened the door turning him into a Pariah for releasing him.

Crisis On Infinite Earths
On December 10, Mobius ordered this army Shadow Demons to attack the Quantum tower located on Earth-38 that stopped the Antimatter wave. Despite the heroes persistence, his army successfully reached the tower and Earth-38 was annihilated.

As more worlds are being destroyed, Mobius powers grew to the point that he could corrupt Harbinger and make her switch side.

When Earth-1 was the only remaining Earth and that his antimatter cannon was destroyed, Mobius sent Harbinger to neutralize the paragons and fight the Monitor on the Waverider. As Mobius controlled Harbinger, he overpowered the heroes and absorbed the Monitors essence to create one last antimatter wave to destroy Earth-1. But before the antimatter wave hit the ship, Pariah teleported the paragons somewhere safe. When Mobius asked where did he sent them, he told him that he won't find then the wave hit the ship.

Trivia

 * His goal is very similar with those of Hunter Zolomon/Zoom, since both of them wanted to  destroy the rest of the multiverse by using a weapon powered by a speedster and rule a single universe.