Quick recap
Barry Allen wakes up in a different world: his speed is gone, his mother is alive, and nobody has heard of the Justice League. The war between Aquaman's Atlantis and Wonder Woman's Amazons has wrecked much of Europe. This world's Batman is Thomas Wayne, who lost his son instead of his parents. With his help, Barry gets his powers back, gathers allies and frees a Superman who has spent his life in government custody. In the final battle, Reverse-Flash reveals that Barry caused all of it by going back in time to save his mother. Thomas kills the villain, and Barry races back to undo the mistake. Reality reforms, changed, and Barry hands Bruce a letter from Thomas.
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