Spike wakes up on the side of an unfamiliar road, with only a confusing memory of the night before and a very unspecific note in his hand. Following the road, he finds himself in the town of Dragonsville, a rural town in the direct center of the country of Serpentia, land of love, tolerance, and harmony. Upon entering the town, he comes face-to-face with the most confusing group of dragons he's ever met: Pinkie Pie, the baker; Rainbow Dash, the stunt flyer; Applejack, the farmer; Rarity, the designer; Fluttershy, the animal enthusiast; Twilight Sparkle, the librarian; and Spike, the #1 assistant, who also happens to be a unicorn, a species most rare in this land.

And so begin the most incredible two weeks of Spike's life...

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Featuring Brand New Cover Art by Ms. Pia-Sama!
MLP: FIM Characters, Settings, etc. © Hasbro & Lauren Faust

Magic is bleeding out of Equestria and into another realm, a realm where magic does not exist. Twilight must stop the flow of magic before disaster strikes. Can the natives of this realm be of help? How do sapient beings function without magic anyway? What's this about a cartoon?

Takes place shortly after season four.

Talks broke down. The unification failed. Hearth's Warming have never occurred. The Great Pony War divided the land, and fears of a prophecy forced the unicorns deep underground and into near extinction.

Almost one thousand years have passed. The curious unicorn Sparkle yearns to breach the surface to discover its many wonders and to search for her missing father and brother, both of whom crossed over many years ago. She is forbidden to leave the safety of her subterranean village of Unicornia until she discovers an orange earth pony washed up on the shores of an underground river. That pony bears one of the six Elements fabled to change the world.

Or destroy it.

Cover art credit goes to ouyrof.

Re:Harmony was conceived before Season 4 aired, so some personalities and character relations do not line up with the show's canon.

Also, please refrain from revealing spoilers in the comments. Thanks!

This story is a sequel to Split Second

Twelve years ago, she broke time. Two alternate timelines exist, each with a different version of Twilight Sparkle. Both versions of her are able to see the other. In this timeline, Sparkle is a Necromancer.

Or rather, she was. Sparkle is dead now, not that she cares. She's got a new body. With Thorn (her undead dragon son) and Cobalt (her apprentice and an assassin for hire) at her side, she's ready to take on the world. Again.

(Spoilers in the comments. Read at your own risk.)

Featured on EQD.
The Tv Tropes page
The Ask Blog

This story is a sequel to Split Second and won't make sense without it.
This story also loosely shares continuity with Lupine Tree. Reading that is not required.

Cover art by Swirling Line.

Twilight Sparkle broke time when she got her cutie mark. Now Twilight and Sparkle are sisters from another time. Twilight is hailed as the potentially greatest light magician of all time, and already has a reputation as a hero by the time she goes to Ponyville. This isn't her story, not primarily.

Sparkle is an orphan - her dark magic killed her parents. She lives with her brother in Canterlot's industrial sector because they can't afford anything better. She can't leave either. She's a natural dark mage; while Sparkle won't go mad like Sombra, her reputation is hardly any better. Worse, the law doesn't see her as a good pony.

The fact that the dead don't stay dead around her, or that Thorn - Spike's double - is an undead, soul-eating abomination, are other matters altogether.

(Also has some Slice-of-Life, but fimfiction tags won't let me put it with Adventure.)

Has an ask blog to go with it: Ask Sparkle and Thorn.
Also has a TvTropes page: Split Second Tropes.

Featured on EQD.

Cover art by Swirling Line.

It had been a very nice day. Ponies worked, played and laughed. Wherever you looked all was well. The young pony, recently given the title of 'Princess' was just sitting out enjoying what life had to offer. Then everything changed, and it did so with a cube...

Lost in a plane completely foreign to her, Twilight Sparkle must use her skills as a leader to guide a whole town to safety. Now is the time the young Alicorn must prove her worth as a leader. Over a thousand ponies are lost to an unforgiving, eternally unchanging world. Can she save them all?

The fourth great ninja war was over. With Sasuke's help, Naruto vanquished Madara and defeated the Juubi. However, when all was said and done, the two were betrayed by those they trusted most. Fearing the outcome of the toad elder's prophecy, The survivng kages threw Naruto and Sasuke into time and space with the hopes of banishing the two forever. The two however, manage to end up in an entirely new world, giving the two a possible fresh start. Their arrival however, changes the outcome of upcoming events in this world in ways that should never have happened.

It was an ordinary day in Equestria. The sun was shining, the birds were singing and princess Celestia had some free time from her royal duties. Then the explosions started, explosions originating from the Everfree Forest.

Cover art supplied by RainbowDashVegetaFan123