Princess Luna is an Alicorn pony and the younger sister of Princess Celestia in My Little Pony: Friendship is Magic. She raises the moon and protects ponies' dreams. A thousand years ago, bitterness over ponies ignoring the night transformed her into Nightmare Moon, who sought eternal night. Celestia banished her to the moon using the Elements of Harmony. In the series premiere, Twilight Sparkle and friends defeat Nightmare Moon, restoring Luna. She reconciles with Celestia, resumes duties, and later retires with her sister to Silver Shoals after Twilight becomes ruler.