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Original Description:
 
Princess Celestia’s younger sister shares responsibility for ruling Equestria with her. When afternoon grows long, it is Princess Luna who raises the moon so night can come and the ponies can rest. Long ago, She once let bitterness overtake her heart, twisting her into the evil Nightmare Moon. But thanks to the power of the Elements of Harmony and the magic of friendship and forgiveness, Princess luna reigns by her sister’s side once more. Her most interesting job to date is entering ponies’ dreams and help solve their problems and offer guidance.