Luna Skywish's life changed one fateful day as a filly when her best friend Starswirl was sent away to explore the talent his cutie mark signified. Having already lost her older sister for similar reasons prior, this was the final straw for little Luna, who decided cutie marks brought nothing but misery to her and any other pony, even if they didn't know it yet.
Though naturally a more sarcastic and somber pony, Luna quickly learned the best way to get ponies on her side was to feign saccharine cheer and friendliness. Through this false persona, she was able to establish her own little village in Our Town, where ponies lived in peace and harmony without the troubles cutie marks brought—or so she thought.
After being defeated (twice) and learning the true value of friendship, Luna would become the student of Princess Fizzlepop Berrytwist herself, better known to her friends as Tempest. Able to at last make true friends of her own who liked her for who she really was and not a falsehood, Luna dropped her fake cheer and let her true snarky nature shine through—and, much to her relief, she was loved all the same by her new friends.
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Luna's older sister, Celestia Skywish, was talented enough in earth pony magic to be noticed by Princess Adagio once upon a time. The Princess quickly took the earth pony under her wing as her personal protege, much like Tempest would eventually become. Unfortunately, Celestia's ambition was too strong, and she ended up trapped in the world beyond a magic mirror after a particularly vehement argument with her teacher. There, she would use her charisma and manipulation tactics to rise to the top of the local high school.
When Tempest later came to Canterlot High in search of her stolen Element, Celestia learned the true power of friendship and started down the path to redemption after her defeat.
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