A friend of mine mentioned to me that in every episode, even after the first two, there is a mare on the moon. He may have just been mentioning in Scootaloo's nightmare, but what if he's not? Maybe, just maybe, the Elements took the Nightmare Moon part of Luna, and sent it to the moon. Now, as you all know, the element's effects never seem to last more than 1,000 years. So maybe Equestria will have a visit from the Queen of the Night in just a short thousand years.

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Can't wait for season 1000 then (assuming each season takes place in a separate year of course)

2699374 lol But everyone but Twilight, Luna, Celestia, Discord, and Spike will be dead.