In this behind-the-scenes explanation of the Mare in the Moon incident, follow Nightmare Moon and Princess Luna as they encounter strange, artificial beings from another world. A Portal 2 crossover. Contains two stories:

Of Cores and the Alicorn: After what seems like an eternity, Wheatley and Nightmare Moon cross paths and discuss their respective exile in space.

Guerrilla Corefare: Nightmare Moon is free, but the magical accident that released her did more than just send her back to Equestria. Now, from behind the scenes, Luna exploits Nightmare's newfound weakness in order to sabotage the plans for eternal night.

Note: As older stories (in fact, written before the debut of Season 2), these are fairly amateurish, relatively speaking, and contain speculative-at-the-time characterization for Luna. With the exception of a few minor edits, however, they have been submitted in their original forms for posterity's sake. This isn't Airstrip One, after all, and I don't work for the Party.

After the Changeling invasion, Celestia and Luna make the decision to have Twilight investigate the Elements of Harmony and solve the mystery of their power.

A thousand years later, Rainbow Dash awakens in a world she does not recognize. She has no idea how or why she came to be there. She does not know the language, the geography or any of the rules of this new time. She soon finds allies in Star Fall, a scholarly pegasus whose Talent is Magic, and Astrid, Star Fall's Griffin guardian. Together they set out to discover why Dash has been sent to the future, and how she might return to when she belongs.

War threatens the nations, a Nightmare stalks the shadows, and Rainbow Dash's arrival has turned her into a wild card in a deadly game that pits the law on both sides of a broken Equestria against a mysterious criminal figure, Max Cash. Yet the stakes are higher than anyone knows, for in her research Twilight Sparkle discovered a dark secret about the Elements, something that will shake the foundations of the world.

Cover image by SierraEx
Has a TvTropes page

Curious about Five Score? Come check out the story that inspired dozens of side fics and been enjoyed by bronies for years!

Original Synopsis Even though MLP:FiM ended a few years ago, my friends and I still loved the show. Stories, merch, fan art, I loved it all. Things started to get a weird though when I found myself with a cutie mark appearing on my leg. Humans aren't supposed to get cutie marks, so where the heck did this come from? And what's going on with my hair?

More Detailed Synopsis: Five Score is an action/adventure story of the human-to-pony transformation genre. It’s unique from most transformation stories because the transformation itself is not really the point of the story. It’s the inciting incident that raises countless challenges that must be resolved. They are on earth, as a pony, and need to fix this before things get worse. Think about yourself in their hooves for a moment. How are you supposed to change back or even figure out what caused it in the first place? How are you supposed to get food or do anything on Earth without being spotted by humans? If you are spotted or captured, how would you escape? How does one even open a door with hooves!? Did anyone else on Earth get changed as well? How could you get the word out to the other ponies who are themselves hiding? Is it worth risking travel across the country to reach the others? Which of your friends would you trust to help you deal with this? And why did you turn into this particular pony? Surely it wasn’t random chance, right?

These challenges are the tip of the iceberg in this full length adventure novel There’s a lot of humor, many tense scenes, and hell maybe even a war.

But don’t just take it from me, Look what random people on the internet are saying about Five Score, Divided by Four

One of the best things to come out of this fandom.
-IrraticDrop

This made me change how I think about fictional worlds, imagination, and creativity
-relgukxilef

The only story on FimFiction to have me literally shaking with excitement.
-jeramiahsental

SWEET FILLY LUNA I AM FLIPPING MY SHIT RIGHT NOW
-Shadow Reaper

Five Score master editor:
Scrub

Five Score proofreaders:
Comrade Sparkle
Rustle my Jimmies

Imagine a world (or a crackfic) where everything you know of the ponies is true. Now imagine the ponies living in the universe of Mass effect where magic is just another name for biotics.

The Reapers are coming, but they have never faced anything like the Ponies.

Discord was experimenting one day with teleportation between dimensions. When he tried, however, he ended up sending the Mane 6 to a distant galaxy called the Milky Way. Oops.

Consequences of our actions are often unforeseen. Some are harmless, some are fatal. Some are temporary, some are permanent. And then we have these.

When Rarity decides to perform a little wizardry, it should come as no surprise that things do not go as planned. One thing leads to another, and Rainbow Dash ends up with a stallion that looks, acts, and thinks like her to deal with. Will hilarity ensue? Will relationships form? Will Twilight just clone everypony else and get it over with? All very good questions. Some might even get answered. Tune in to Graphs to find out!

I believe gender-bent characters belong to that Trotsworth fellow. Cover brought to you by roselladoll1. She seemed to express consent for its use. Heartfelt thanks and whatnot to those two.

During a blissfully rare calm in the hectic storm of Ponyville life, a disturbance in the Everfree Forest goes undetected. After receiving a summons from the Princess, Twilight and her friends are led into a curious task, one that they find themselves ill-prepared to handle - managing their stallion double! As each of the girls meets their very own carbon-copy-colt, they learn that dealing with themselves can be much more frustrating than they first thought.

Annoyingly, irritatingly, intoxicatingly frustrating.

http://www.equestriadaily.com/2011/10/story-giving-love-helping-hoof.html

Rainbow Dash has forgotten something very important. Only problem is, she doesn't realize that she forgot it in the first place. A reimagining of Rainbow Factory, now with 100% less unnecessary death!

Cover art stolen from Pika4Chu on DeviantArt.

"We have to be brave now, Scootaloo," Dash said. "Just close your eyes, and it'll be all over by the time you open them again."

Not all assumptions are malicious, but even the most innocent rumours can be unpleasant, if they actually effect ponies' lives. Rainbow Dash knows this all too well as she tries to confront the stallion of her dreams. A bitter-sweet kind of hilarity ensues when she meets another pony with similar problems.
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