Alicorn Pony and ruler of the night. She rules Equestria with her Sister, Princess Celestia . She is first seen in the very first episode as Nightmare Moon, when she threatens to make the night last forever. Princess Luna used to help rule Equestria over one thousand years ago, until jealousy overtook her and she became Nightmare Moon. She was banished in the moon by Princess Celestia when she refused to set the moon.
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