Background Pony #C5E3
There never was a "Nightmare Moon." It was a prank Luna played on her sister, a prank that went too far and resulted in a thousand-year timeout on the moon.
Nightmare Moon and Daybreaker were never meant to be evil. They both were created by a young Luna and a young Celestia back in the day when the races were still divided and Alicorns were seen as mutations or undesirables (Kinda like an imaginary friend). The colossal magical power of the Royal Sisters were enough to bring them to life. This wasn't ignored by the other races, who in fear of "multiplicating alicorns", decided to use a now forbidden magic to darken the hearts of Daybreaker and Nightmare Moon. When Celestia and Luna noticed it was too late and they had to "absorb" them, this is one of the reasons the Royal Sisters want to have the knowledge of all of Equestria's magic; to reunite with their best and only childhood friends and undo the forbidden magic cast upon them.
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