In a universe full of infinite possibilities, Nightmare Moon has ruled Equestria in Eternal Night for one-thousand years. But when she is shown a vision of a world where ponies live happily in sunlight and where Celestia still holds dominion, she begins to fear for her crown. With the aid of powerful magic and an entire army behind her, she lays siege to the other world.
The tear in the fabric of reality threatens to unleash even more unspeakable horrors, and when Spike goes missing, Twilight Sparkle and the Bearers of Harmony must cross to the world of darkness and find themselves to help close the portal linking the two worlds together.
But in this new world, not everyone is who they seem....
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