[Complete! With TVTropes apparently!]
Also, apparently, an animated trailer.

In a world of brass and steam, Twilight Sparkle had thought she had made a life-changing discovery with the invention of the telescope. For better or worse, she was correct.

Now her discovery has not only changed her life, but the lives of those she seeks out in her desperate attempt to contact the only other creature as lonely as Twilight herself.

It all would have been much simpler, but it had to be the one Twilight could only call The Mare on the Moon.

Decidedly not within walking distance, then.

[Featured on EQD before story was meant to be submitted. 4/03/2015]

[Editing team: Southpaw, Wolfvenom, Maskedferret, SwanSong and BluePaladin42, without whom this story would be a fraction of its current state.]
[Special thanks to Novel-Idea for the updated cover]

SF (canon species only; no humans) Ponies were magically and genetically engineered to be the perfect servitor race. They are powerful, adaptable, intelligent and completely under the control of their creators. A laboratory accident frees one such pony from her mental chains, but how can one mare save herself and the rest of her kind if she doesn't even know she's a slave?
This is not the Equestria you know and these are not your little ponies... not yet, anyway.

Tags: Adventure, Diamond Dogs, Gryphons, NO HUMANS (did I mention that already?)
Other tags: historical, mind control, Clarke's 3rd Law, excessive use of high energy physics, before they were famous.
Detailed review by PaulAsaran.
Cover art by endrome , used with permission.
Russian translation (partial -- 'unofficially' completed in the comments)
A Soot-Covered World, book 1.

This story is a sequel to The God Empress of Ponykind

A message rings through the Warp: "The Game is broken, only Destruction remains". Celestia hears it, fearing for the lives of her former subjects and those of her beloved ponies. Unwilling to sit idle, she has chosen a dangerous path: return to the Imperium, take up the mantle of Emperor of Mankind, defeat the coming storm, and save Mankind once and for all.

With Twilight Sparkle to aid her, Celestia faces new challenges and new enemies. Her forces are scattered, her people assaulted, and the enemies of Man grow stronger with each passing day.

The Time of Heroes is gone. Now comes the Time of Ending.

Sequel to God Empress of Ponykind. Reading that first is strongly recommended.
Rated T for 40K related violence, but that might change at some point.
Comments contain spoilers. You have been warned.

This story is a sequel to Days of Wasp and Spider

Believed dead by their creators, the ponies that will become Celestia and Luna have broken their mental conditioning and escaped into the wilderness. Here they plan the revolution that will free all ponykind, knowing that it is only a matter of time before their ruse is discovered.

Back in their underground arcologies, the ponies' erstwhile masters deal with the consequences of the escape, all the while unaware that something lurking at the bottom of space-time wants them all dead.

A Soot-Covered World, book 2.
Canon species only/no humans.
This story has nothing to do with the Holocaust.
Art by InLucidReverie, used with permission.

Twilight Sparkle wakes up one morning to a harsh dose of unreality. She is stranded, without her friends, on an island which matches no known locale on Equestria. Surrounded and harried on all sides by the alien and the dangerous, she will find her mettle sorely tested, and find perhaps that the best friends you will ever have in your life are the ones you make when your back is to the wall...

Thanks to CedricBale and noobie56xx for tracking down the name of the artist so I could give them credit.

In 2185, during his campaign against the Collectors, Commander Shepard discovered a previously unknown species whose origins predated any other race in the modern galaxy. Following a daring rescue from their ancient sanctuary, the Equestrian Herd was brought back into the galaxy where, for the first time in eons, they must walk their own path.

Knowing full well the terrible threat that lingers on the edge of the galaxy, the leader of this newly freed race fights to secure her people’s future while attempting to prepare for the storm on the horizon.

This is her story.
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The long awaited Sequel to Mass Effect 2: The Equestrian Equation This is a reader directed story. Your choices will shape events.
If you favorite, also like! It's one little button click that makes all the difference.

Also, this series has its own TVTropes page now! (Special thanks to user CrowMagnon for setting it up).

A mother will do a lot for her child, even give them up if it meant them having a safer life growing up, despite the obvious pain that comes for the parent.

That pain is something Queen Chrysalis has gone through for eighteen years, but now the time is upon them, and she wants her daughter back. Even if that means invading Canterlot during a royal wedding.

Edited by RC2101_Copey
New cover art was created by the talented Jesuka
Now has a TVtropes page: http://tvtropes.org/pmwiki/pmwiki.php/Fanfic/Change
Go watch the reading by Skijaramaz: https://www.youtube.com/watch?v=Ecqtu_Djrw4

(Featured on 18/10/2015, the first day! Thank you!)

Change is now a printed book, information here: https://www.fimfiction.net/blog/732008/i-got-a-thing-change-is-now-a-physical-book

"I have sworn upon the altar of God, eternal hostility against every form of tyranny over the mind of man."
-Thomas Jefferson

Three hundred years ago, Equestria tried to assimilate Earth.
They failed. They fled, rather than face justice.
We moved on. We conquered the stars, we made a civilization that spans across the infinite void. We built true harmony between species.
We thought we'd seen the last of Celestia, but as a desperate mobile colony on the fringes of known space came to discover, we were wrong.

It is time to finish what was started by our forefathers.

Based on TCB: Not Alone, by Starman Ghost.

EDIT: Following Starman Ghost's deleting of Not Alone, I've replaced the above link with one leading to a PDF file uploaded to mediafire.

EDIT (14/04/2014): The character of Evening Star was originally created by Starman Ghost. I am using her without his permission.