Princess Luna



"Boy, I don't know why Princess Luna was once Nightmare Moon back then when she was being so bad to everypony in Equestria since then, but... yeah, she's got the Elements of Harmony to restore herself back to her good ol' Princess Luna so she can rule the land with her sis named Celestia. I don't know why Canterlot is about to fall..."

--Su Ji-Hoon, Equestria Has Fallen

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 of My Little Pony Friendship 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.

In When the Cold Breeze Blows Away, due to helping her old sister, she will joined the Grand Alliance after both of her and her old sister ruled Equestria in during World War III.

Therefore,she had choice to control her royal armies to protect Equestria,herself and all of her ponies from new enemies. Or she will help the Grand Alliance.

Until the USRAC War, she was completed with her defensive with the Grand Alliance and Equestrian pony militias. Even though failed to defend Canterlot and made her old sister has been captured, she will find ways to research on the cause of Battle of Canterlot so that she will following the way of Mane Six to being resistance.