A spin-off from the Sombra universe we are able to see in the season 5 chapter finale. The war ends by making a treaty: Luna would stay in the Crystal Empire by marrying Sombra, and peace would come with the end of the war. Luna&Sombra pairing
Princess Luna disappears from Equestria with hopes of saving the world and is accompanied by the enigmatic Sombra. Meanwhile, Celestia tries to bury secrets as immortal as she is and Cadance must choose her loyalties carefully...
Do you remember the three nights of darkness when Luna refused to raise the moon and bring out the stars? It was a thousand years ago, but her heart will never heal nor forget.
When Luna learns to make new friends,the darkness of others hearts threaten them all! It's up to her and her sister to save Equestria! But what if her sadness leads her onto a dark path? Will she fight? Or Will she refuse?
Regretting their last encounter, Sombra wishes to try to make things up to Princess Luna... but isn't the rule "once bitten, twice shy?" He has a long way to go...
They say Luna turned into Nightmare Moon soon after she and her sister had taken down the Tyrant King Sombra. What they don't know is that it was more than just a coincidence. He was once the pillar that held her up. She was too much for one to bare.
A thousand years ago, Luna and Sombra's love was unbreakable. But when fate and Nightmare Forces cruelly conspired to pit their noble intentions against one another, an entire empire vanished from the face of the world.
What would life be like if all of Equestria's villans roamed free? If Nightmare Moon defeated Celestia, Sombra ruled the Crystal Empire, and changelings were a daily threat. Oh, and Discord wasn't a statue.
When two unlikely ponies, Luna and Sombra, meet beneath the silver moon, will their love be everlasting, or will the darkness lurking in the Crystal Empire succeed in destroying them?
AKA Equestria Rises: the Two Sisters. Celestia and Luna are the daughters of Selena and Solaris - the high priests of the Castle of the Sun and Moon. Life changes drastically, as they are gradually introduced into a world of kings and magical tyrants