My Little Pony: Friendship Is Magic

The Beginning of the End (1) (9x1)

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When Celestia and Luna decide to retire and hand off the ruling of Equestria to Twilight and her friends, it sends Twilight into a tailspin of self-doubt. Meanwhile, the ancient villain Grogar bands together a legion of nefarious characters to conquer all of Equestria, but a restored King Sombra has conquering ideas of his own.