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Original Description:

More weirdness at Canterlot High School has befallen Vice Principal Luna. It appears that some new evil is talking the hall of CHS.

Princess Luna, known as Nightmare Moon or Night Mare Moon when transformed or under certain other circumstances, is an Alicorn pony, the younger sister of Princess Celestia, and the main antagonist of the season one premiere My Little PonyFriendship is Magic as Nightmare Moon. She is also the adoptive aunt of Princess Cadance. Eventually, the Elements of Harmony restore Luna to her former self and she returns to rule over Equestria alongside her older sister. Princess Luna/Nightmare Moon is called by her respective early names Princess Selena/Night Mare in another depiction.

Vice Principal Luna is a female human and Princess Luna’s human world counterpart in the My Little Pony Equestria Girls film series. She is the vice principal of canterlot High School and younger sister of Principal Celestia.