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.

Rainbow Dash flies east.

UPDATE: 8,000 unique views! Wow! I'm incredibly flattered!

TVTropes Page

Plowpony's Day- a day of peaceful rest and relaxation. Or it was, until Twilight Sparkle badly mangled a teleportation spell. It has left her with a bad case of Horn Rot, a disease that if untreated could prove fatal. What's more, the malady is advancing faster than the slow-brewing potion that cures it!

There is one swifter cure: the Beneviolet, a star-shaped flower that grows in the distant Archback Mountains, far beyond the western borders of Equestria. Applejack, Rainbow Dash, and Rarity choose to undertake the long journey for the sake of their friend. Their path will wind through floes of ice, across gold-tinted plains, into distant forests glimmering with magic. They will learn much about the world beyond their homeland- and much about themselves, as well.

Yes, it's "Dangerous Business," here on FIMFiction. A huge debt is owed to all those who have supported me over the years. I've edited the story some to remove extraneous bolding and italics, but other than that, it remains unchanged. I hope new readers enjoy it as much as old ones did.

TVTropes Page