Twilight Sparkle is called away to tend to Luna when she falls ill. As Luna grows sicker and Twilight more determined to help the younger princess, she begins to uncover dark secrets about the elements, the alicorns, and her own past.

For almost a thousand years, the immortal Nightmare Moon has reigned over Equestria as Empress. To the average pony, Nightmare Moon is an overarching enigma whose rule is absolute and whose wrath is terrible. But to Twilight Sparkle, who as an orphan has never known her parents, the Empress is something else entirely. When the young unicorn is brought under the royal wing as an apprentice, she learns a great deal more about the supposed tyrant than she ever knew. But as Twilight is introduced to life with her new mentor, she is thrust into a world of political intrigue, conspiracies and secrets. Secrets that were never meant to be revealed. As allies and enemies plot against the very peace of the nation, will Twilight fall prey to the perils of her new position? Or will she prosper and find in Nightmare Moon the mother she never had?

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My eternal gratitude to my editor, LordOfTheWrongs, without whom Night's Favoured Child would not be the story it is today.

Now with added TVtropes!

Celestia leaves to deal with a foreign crisis, giving her sister a chance to rule alone and become more attached to the modern world. She calls on Twilight Sparkle to advise Luna, hoping her student will be able to draw Luna out of her shell. With two major threats to Equestria already defeated in the past year, it seems like the perfect time to let Luna gain some confidence and experience in the modern world. After all, what are the chances of a third disaster occurring?

Now comes with complimentary tropes.

Twilight is invited to Canterlot to compete with some of the greatest magicians in the world for the Moonstone Cup, a prestigious award for the most powerful and skillful magicians, unicorn and otherwise. Can she win? What sort of competition will she face?

Awesome cover image was taken from NoOneBahtim

Many years after sending her beloved protege to Ponyville, unease sits heavily on Princess Celestia's heart as her relationship with Twilight Sparkle seems to have cooled despite all they've accomplished together. On the advice of her sister, Celestia sets out to investigate and resolve the lost connection with her most faithful student. What does it mean to be a Faithful Student...or a Princess of the Sun?

Earned a six-star rating on Equestria Daily and featured on its very own TVTropes page!.

This story is a sequel to Off The Edge Of The Map

When Twilight is sent with Luna on a diplomatic mission to Draconia, they quickly find themselves somewhere that doesn't appear on any map, and Luna is lost in more than one way...

Thanks to RBDash47 of Pony Fiction Archive for formatting it for submission.
Title image by Valcron

Tremendous thanks to Illya Leonov and Scribbler for the Audiobook version.
Now with a Spanssh translation by SPANIARD KIWI: https://www.deviantart.com/spaniard-kiwi/art/Apoteosis-2-3-857110089

Princess Celestia lies unconscious without explanation… And the sun refuses to rise. Desperate, Luna calls upon her Sister’s faithful student for help in an effort to enter the Princess of the Sun’s mind through a dreamscape to find the cause of her mysterious coma.

But once they enter, finding themselves in a place of magic itself, a place where a pony’s fears, dreams and histories manifest themselves as worlds of epic proportions, are the two mares ready for what they find inside?

An action fantasy novella.
Featured on EqD!

Deep in the earth, a shadow grows in strength. The Gates of Tartarus are breaking. The fires of revenge are burning.

A lone prince, a traitor to his kingdom, is waiting. He is waiting for power, waiting for the dawn of his new day. Yet the moment his victory is all but ensured, when Twilight Sparkle herself lies helpless before him, the prince starts to forget the line: the difference between who he was, and who he is now.

Can a traitor ever be anything more?