This story is a sequel to Stardust

Times are changing for Equestria as Twilight’s return brings with it news of people and cultures from beyond the peaceful world everypony knows. Aid and volunteers are freely offered to help the besieged humans of Earth because every Equestrian knows that’s what good friends do. Unfortunately, making friends can also have the unintended consequence of making enemies.

When the monsters besieging the humans strike at Equestria with a level of brutality not seen in over a thousand years, the cry for help is sent to all the kingdoms of the world. Honored allies step forth to fulfill ancient treaties and oaths. Enemies, old and new, bury their grievances. An alliance never before seen in Equestria will be created to combat the monsters from the void.

And because of these events, a grim but welcome sibling to the XCOM project is born.

(XCOM/FiM Crossover)
(Sequel to Stardust, which I recommend reading before starting this. Fortitude Amicitia and Broken aren't required reading but are supplemental to the storyline)
(Gore tag for blood and violence)
(Alternate Universe tag because of the divergence from canon that Stardust has caused)
(Uses elements of Season 4)
(Coverart produced by the amazing Carnelian!)
(Many thanks to Arzoo, BradTheBrony, Vandenbz and Setokaiva for prereading!)
(As of 03/07/2016, the prereading team consists of Arzoo, BradTheBrony, Noble Cause and Metallusionsismagic!)
(Complete with it's own TVTropes page as part of the Stardust continuity. Could use some updating!)
(Character tags will be added as chapters are added!)
(Featured 5/12/2014! Thanks folks!)
(Possible spoilers in the comments! BEWARE!)

This story is a sequel to Abandon All Hope, Ye Who Enter Here

What do you get when you place a pompous, prissy and petulant prince with an absolutely insane former extraterrestrial individual with a bad case of Chaos?

Love, adventures, spying, strong desires to strangle the other, romance, lots and lots of foals, grimdark, pudding, cults, injustice, justice, strong friendship, weak sanity, history, stories, a rocket jumpsuit, three opportunities to take over the world and a cockatrice. On Sunday.

Things… You get things.

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And when you're especially lucky, you get a great cover art from an artist like Mix-up (also seen on fimfic here)

After a fleet of Separatist ships reactivates over Muunilinst at the end of the clone wars, a single Providence-class Dreadnaught escapes into unknown space in a randomized jump, and the Battle Droids on board meet everyone's favourite pony princess. Join Princess Twilight and friends as they try to make sense of the giant metal bathtubs from the sky and their strange occupants.

(Big thanks to my friend Dawny and my new editor Mine_Menace for editing this story for me, as well as Zaten for helping me proofread on later chapters)

WAIT, WHAT? I got featured? 05/27/2019
And apparently again 08/07/2019

This story is a sequel to A Pony out of Place

Set directly after A Pony out of Place. Flare Blitz, a Rapidash, turned pony, has opted to stay in Equestria, but things won't be so easy for him. Now a full-fledged pony, he has to earn a Cutie Mark, train with the Princesses, survive a love triangle and Arceus knows what else.

And most importantly... get Twilight to go out with him!

It has a TV Tropes pages too, check it out and help add to it.

In the magical land of Equestria, two alicorn sisters raise the Sun and the Moon every day to give the world a night and day cycle, basic for the survival of life. There are also two alicorns who rule over two very core aspects of life and harmony itself. Those are Love and Friendship. While not as ancient as the two sisters, all princesses are essential to the world's balance.
This balance is also sustained by the hard-working ponies, who make the seasons change and manage the weather to fit their needs, so everypony has enough food and water, and every animal is also attended to assure that any of them are caught in the changes of seasons.

But what about the planet itself? What about Mother Nature?
This is the question that Gaia asks when she arrives to this foreign world. After so much work her son persuaded her to take a long vacation in Equestria, saying that she needed one and assuring her that he would be in charge now, and she must take a break. But what can a several billion-year old alicorn possibly do to pass her time in this land?

(SimEarth/MLP Crossover)
(Timelife of Gaia's life 'till the start of the story)

Now with an amazing YouTube reading by the equally amazing AShadowOfCygnus!

During its two year search for Shepard, the lone Geth traveled across the galaxy, exploring worlds both known and unknown. After a blind FTL jump to escape from an Alliance patrol, it found itself in a previously undiscovered system, a system without a mass relay and completely cut off from the rest of the galaxy. It touched down on one of the worlds, a garden-like planet, with the intention of gathering data on any flora and fauna that may have been present.

Instead, it made a remarkable discovery.

Edit at 8:10 AM on 8/17/2014: Scanning...Featured Box Achieved! This unit humbly thanks all organics and fellow synthetics for their support!

A big thanks to my bloody brilliant proofreader AShadowOfCygnus. Don't stop being classy, buddy.
NOTE: This story takes place years before the Return, back when Twilight was just a filly.
Disclaimer: I own nothing.
My Little Pony: Friendship is Magic belongs to Hasbro.
Mass Effect belongs to BioWare and Electronic Arts.

This story is a sequel to Starswirl and the Purple Terror

After the events in the past, Twilight can't help feeling dejected. She would never see Starswirl again. Or at least, that's what she thought right before he came knocking at her door. Meanwhile, in the past, a still somewhat immature Celestia is desperately trying to find a way to deal with the unfolding catastrophe. Luckily, her spymaster is always there, ready to lend a helping hoof.

Author's Note:
See what you made me do! I hope you are all happy... because this can't end well.
Also, you can't really read this without reading the previous story.
Full credits to Sorrowfulwinds for the title name.

A few years after retiring, Celestia and Luna went on an extended vacation to see the world and broaden their experiences. Now, almost forty years later, they have returned to their roots in Equestria, at least for a while.

Four decades is a long time, so Twilight and Celestia decide to catch up over tea. However, it seems that Twilight has changed more than Celestia expected.

Cover by Nnaly.

Name's Storm. It's my title, my alias, and my identity.

I've been fighting for centuries now. Thousands of them, in fact. Traveling from dimension to dimension, trying my best to maintain proper balance. Not too much Law, not too much Chaos. Not too much Good, not too much Evil. At the same time, I am different. I have something that's unimaginable. Something that strikes inspiration in allies, fear in enemies, and horror in Gods themselves. A piece of interstellar technology I so aptly named the 'Universal Editor', a device that enables me to 'edit' the Strands of Existence, which then allows me nearly impossible feats.

After a close-encounter and failure to perform my self-imposed duty, I escape with only a flesh wound (or seven). Only to fall right into a realm packed with mythological beings, heavy emphasis on peaceful environments, and colorful technologically-inept equines that constantly try to become closer to me. Let's see how far my remaining sanity will plummet after this...

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Rated Teen (Good amount of swearing, minor descriptive gore, and plenty of violence)
Story began: January 26th, 2012 (Posted on the 27th)
Editors: ShadowHorizons (Editor-In-Chief), SovietBacon
Cover Art (using Photoshop) made by: SovietBacon (artist of original picture [found thanks to EdwardJ] is this guy.)

(Post-Mass Effect 3)(FemShep)
When the Reapers were defeated, the galaxy believed that Shepard and Anderson were both lost in the final battle. However, the two long-time friends were also known for not letting death stand in their way.

Waking up, in the middle of a desert, on an uncharted planet they both embark on their strangest mission yet. Attempting to find their way back to the Human Alliance, a place called Canterlot may hold the answers they seek. But first, they had to get there while trying not to draw too much attention to themselves.

Too bad for Anderson since massive explosions and collateral damage followed Shepard wherever she went, without fail.

Crossover of My Little Pony and Mass Effect.
Cover image credit goes to: CSImadmax at http://csimadmax.deviantart.com/
Chapters 1 - 6 proofread by: http://www.fimfiction.net/user/GermanDash (Pre-March 2021 update)