Lunar Rainbow doesn’t remember who her family is. When she awoke one day to the sunrise of the Summer Sun Celebration, Lunar Rainbow was lost and confused, with nothing but a faded cutie mark to tell her who she was. That night, when the moon was brought forth, she did the only thing her instincts could allow—she created a rainbow around the moon. Upon landing, she saw her now brightened cutie mark and gave herself her new name.
For several years, she wandered alone through the land of Equestria, unsettling the population of any town she went through without a cover for her wings; they didn’t know how to handle a completely unknown alicorn, and assumed automatically that she was up to no good. Eventually, tired of being shunned by everypony, she built herself a tower deep in the White Tail Woods, only associating with other ponies when she had to, and always wearing a cloak to cover her wings when she did. Every so often, though, everypony stays up late into the night because of a mysterious ring of color around the moon.
When the Running of the Leaves cuts through her beloved woods, Lunar Rainbow always goes onto her balcony to watch. This time, though, she decides to join the other ponies in the festivities. That’s when the blackouts start, and simultaneous reports of a mysterious black mare with a white, swirling mane and glowing flanks.