In an Equestria where Princess Luna was never possessed by the Nightmare the world thrived under both Celestia and Luna's rule. As such, the timeline diverted. After rigorous evaluations, Sunset Shimmer was chosen by Princess Celestia to be her student. Twilight Sparkle, having been glossed over by the Sun Princess, was selected by Princess Luna to be her pupil. One day, the Immortal Sisters send their protégés on a mission to a small town. When the villain named Starlight Glimmer appears all of their lives will be changed forever.

King Sombra, the tyrant of Crystal Empire is back, only to be imprisoned by princesses and put through reformation with Twilight Sparkle as his teacher. Can somepony with heart as black as night be reformed? Twilight believes so. Sombra in other hoof isn't so sure but something in that mare makes him try.

This is going to be one of my longest stories this far. Marked Teen for sexual innuendo and slightly gory-ish scenes. Nothing too bad though. Also this will not be a story that deserves a dark marking.

For now I'd like to thank Alun Aleriksson, pony of change, Microshazm and Sidetrack for helping with the grammar and overall writing in general. Thank you so much.

Cover art by lorekhearts.

After defeating Tirek, Cozy Glow, and Queen Chrysalis with the help of her dear friends, Princess Twilight Sparkle is about to truly ascend to the throne and rule over Equestria in both Luna and Celestia's stead. Unfortunately, her ascension isn't what she was expecting, and a shocking revelation is made.

Foreknowledge of 'Ark: Survival Evolved' isn't entirely necessary, but it does help nonetheless.

Editor: Demondude.

Former King of the Crystal Empire Sombra wakes up in a cell with the given decision between reformation or a lifetime in prison. He accepts with some caution and after some details are sorted out, he is moved to the castle of Princess Twilight Sparkle under reformation.
With all the craziness about the arrival of an evil slave king going through the humble town of Ponyville, Sombra is left wondering what he got himself into.
Can two ponies who hate each other with all their guts become friends and prove that old habits can be changed? It depends on how you define 'hate'...

UPDATE: Under... construction perhaps? It has been years but... maybe I'll update this. After I rewrite every chapter, of course.

Searching for any records King Sombra may have left behind, Twilight learned of the shadowy king's tragic past. However, she also discovered his horn, in which his mind and remaining power were contained. Determined to learn how to use his Dark Magic for Good, Twilight brought Sombra back to Ponyville with her. After all, what could he possibly do as a horn? ...Or will he stay that way?

Edited by Darth Vendar and Myrkur
Inspired by Issue #1 of FIENDship is Magic
Gore tag just to be safe.

Edit 06/15/23: Now in the top 2K stories on the site, by rating! Thank you all!

When Twilight starts blacking out and sees a figure cloaked in darkness she starts wondering who or what he is when she seeks help from Cadence she looses control and almost hurts her, with dark magic no less. Twilight doesn't dare go to Princess Celestia for help, Celestia wouldn't understand so she turns to the pony in her head. When she does, she sign's her soul to the King of Shadows, King Sombra. Her old enemy becomes her teacher and makes her do things to others she never even dreamed about. Twilight has gone off the deep end can her friends save her before it's to late?

This story is a sequel to Lost into Shadow

Twilight has failed, or rather, she has succeeded. Her darkness is her power, and together with her husband, Queen Twilight has a new plan for all of Equis. The black castle rises to greater power than has ever been seen before. War is brewing while alliances are forged and others are broken. The days of harmony are dead and gone, and all the world will be forced to mobilize against the might of the Nightmare Hordes. Will they prevail in the faces of Wrath and Despair? Do they have any hope of someday returning to a time of peace and love?
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Not a chance, because in Chapter 1, Hope dies.

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!

...have a tendency to go awry in the most unexpected of ways.

When the Crystal Heart's power destroyed King Sombra, all of the Empire rejoiced. Little did they know, they had played right into the ancient tyrant's hooves.

Having over a millennium to plan, Sombra knew that if a pony managed to get past his traps before he could reconquer the Empire, their was little chance of him surviving. So, he let himself be 'killed', in order to get closer to his true goal undetected; the Umbrum trapped beneath the Empire.

Hiding as just his horn, Sombra laid low in the very heart of the Crystal Palace, biding his time, until the entrance to the underground section was opened by the new Crystal Princess and another princess with a purple coat and familiar magic. Recognizing that magic as that of the pony that foiled his most recent efforts, and knowing of only one princess-to-be with a coat that color, Sombra swears to make Radiant Hope pay for moving against him once again.

Using his magic to reach the deepest depths beneath the Empire, Sombra reached the sealed Umbrum undetected, and reformed his body. Having devised a way to free them during his own imprisonment, Sombra began so, fulfilling his goal even without controlling the Empire. Bursting free in a wave of shadow that left no doubt of their return, Sombra gives Cadence a message for Celestia before following his own subjects into the night:

“Give this message to the Two Sisters. Deliver unto me the princess that yet again hindered my efforts to free my people to me within a week, that I might exact my revenge against that traitorous Radiant Hope, or I shall show all of Equestria why the Umbrum were so feared!”

However, when a week passed, and Sombra found out that the princess in question was not Hope, but rather a new princess named Twilight Sparkle, he finds his plans for revenge derailed. Bound by his word, when she offers to go with him to prevent a war, he finds himself with a 'prisoner' against whom he holds little ire.

And as time passes, Sombra begins to see that he and his 'guest' have more in common than he initially thought.

AU as of Chapter 34 of the 'Friendship is Magic' comics.

Twilight Sparkle, Clover the Clever, Rarity, Princess Platinum, Fluttershy, Private Pansy, Rainbow Dash, Commander Hurricane, Applejack, Smart Cookie, Pinkie Pie, Chancellor Puddinghead. Twelve unexpecting friends on a strange mission in the name of friendship.