This story is a sequel to Twilight Sparkle of the Royal Guard

Between castle gossip, professional rivalries, a blooming romance, and a mysterious malefactor still at large, Decurion Twilight Sparkle has a lot on her plate. Hopefully, she'll make a few new friends as she moves towards the destiny she's chosen for herself.

As per usual, big thanks to Magello for the rad cover art!

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.

When Princess Celestia asks Twilight to make an official, royal visit to Romaneia, Twilight dreads the inevitable succession of dry, boring diplomatic events. The charming Lord Bela soon wins her over, but Twilight is about to discover that all is not as it seems in Bela's apparently peaceful castle. (A story inspired by Carmilla, Dracula, and other classic vampire tales.)

Written for the BadassTwilight = Total Domination Twilight's Nightmare Halloween contest.

(Spoilers in comments.)

This story is a sequel to What Have You Done?

Chrysalis, the Changeling Queen, has taken her prize, unhindered by Equestria's precious heroes. Celestia is little more than another prisoner of war now. The Bearers of the Elements of Harmony are lost, and the Elements themselves have turned away from Equestria's plight. As the world they once knew begins to crumble, a single question is asked among the people as they look up at their fallen heroes.

There is no such thing as "miserably ever after," for someone will always be fighting for things to change. Hope doesn't die just because someone's turned off the lights. Truth doesn't vanish when deceit begins its reign, and Harmony can only shine brighter among chaos.
Even as this world falls, we'll work to build it up again.
Even as you lose yourself, you can find greater things within you.
Even as fear rises up like a tidal wave, we'll forge a sanctuary to stand against it.
Even as you break, someone will always be standing there next to you to carry you through it.

Cover art is by Odin-odin.
Story theme (Equestria in Grey) is by Omnipony.
Main Characters are Twilight, Velvet, Discord, Nightlight, Luna, and Chrysalis, in that order.
See you in the comments, my dear readers.

During the Discordian Era, Chaos ran free, allowing many monsters to establish solid footholds. Footholds that were lost when Celestia and Luna cast down Discord and took his place as the rulers of Equestria. Now, many thousands of years later, the Elements of Harmony, the very same tools that struck down Discord, belong to six individual ponies. Six vulnerable ponies. An ancient draconic vampire begins his campaign of revenge, uncaring of who is caught up within it. His first target? The Element of Magic, student of Princess Celestia, Twilight Sparkle.

Art by Archonix Source is in the link, and he does do commissions.

Twilight Sparkle, becoming anxious at the upcoming Summer Sun Celebration, which she believes marks the return of Nightmare Moon, beseeches Princess Celestia to do something about it.

Celestia, however, has another, more important task for her; making sure that the Summer Sun Celebration goes off without a hitch. Every year, a different town is chosen to receive the honor of hosting the grand festival.

And the lucky city chosen this year, for this fateful holiday, is none other than the city of Manehattan...

Cover image by Conner Cogwork.

Manehattan is an old city. There aren't many surprises or mysteries left in it, except for what mysteries the ponies that live there make.

But sometimes, mysteries have a way of making themselves. When one of their own stumbles across such a mystery, the Elements of Harmony need to decide what to do about it...

Set in the Manehattanverse.

Spike has taken the hobby of reading Daring's exaggerated readings of her many adventures. One day when Daring has to go and uncover a lost jewel; He, Twilight, and Trixie tag along on one of her adventures. Where as Spike should never judge a book by its cover.
Set in the Manehattan Universe.
Takes place one month after Brag you down.
Cover Art by: punzil504

Sequel to 'Always connected' that follows Rainbow Dash and Applejack as they enter the war that was started because of Gilda. They learn about all of the sacrifices that the other elements of harmony made, while at the same time coming to grips with new powers in order to fulfil an ancient prophecy that indicates that they are the ponies destined to end the war... or die trying.

Trixie has never been one to shy away from boasting and ego stroking. It certainly helps when you've suddenly become one of the most important ponies in the world in the span of a single night. But Twilight starts to think things are getting out of hoof for the showmare when she starts hoofing out autographs and getting news columns for things as simple as stopping a runaway baby carriage or fixing a broken carriage wheel.

So she decides to show Trixie what a real hero is like with a little help from her friends. Unfortunately for them, everything will go too according to plan. When a simple scheme to teach a mare about swallowing your pride turns into a race to save a reputation, a friendship, and perhaps an entire city, there's only going to be one question on everypony's mind at the end of the day:

What truly defines a hero?

Story set in the Manehattanverse.
Cover art by punzil504