PAST:

PRESENT: Twilight Sparkle's reckless testing of Star Swirl's unfinished spells continue, this time with whole new consequences for Equestria.
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Equestria is a land filled with happy content ponies, but it was not always so. Just a few millenium have passed since the Triaarchy of the three tribes prosecuted the small Human/Pegasus/Earthpony nation of Vinland. A land no one remembers, but who remembers everyone else. A land whose Human Princess just disappeared.