Battle at the Dawn of Time (Antimatter Universe)

The Dawn of Time was where the Multiverse was first created.

History
After Mobius destroyed all reality across the entire multiverse, and Pariah sent the Paragons to the Vanishing Point, Oliver Queen came and got them and told them in order to stop the Anti-Monitor they needed to travel to the dawn of time. After Oliver successfully defeated the Anti-Monitor, at the cost of his own life, he lit the spark for a new multiverse to be created, the seven paragons then used what remained of the Book of Destiny to recreate a new multiverse, resulting in Earth-Prime.