A flip of a coin. A twist of fate.

Twilight Sparkle, younger sister of Princess Celestia's personal student, Shining Armor, grew up listening to her brother's bygone dreams of joining the elite of the elite: The Royal Guard.

Now, fresh out of the Academy, this young mare is ready to prove herself equal to the deeds of the great soldiers she read about as a filly. Too bad the princess she ends up protecting isn't Celestia.

Following the destruction of the Collector Base, the crew of the Normandy-SR2 go their separate ways. One squadmate, an AI 'Geth' named Legion, is sent by the Geth Consensus to investigate the possibility of a Quarian attack. However, when Legion is discovered and forced to make an emergency jump through the Mass Relay, it finds itself in the most unlikely of places... Equestria.

At the same time, the ponies of Equestria are dealing with their own problems. A mysterious disease threatens to topple pony civilization, while tensions along the border are growing and could escalate into full blown war.

Join Legion in its journey in Equestria to both return to the Geth before the arrival of the Reapers, and to help the peaceful ponies who inhabit the world.

Notice: As of 9/12/2016, this fic has received comprehensive updates to grammar/spelling/sentence structure, with a few minor plot alterations. Enjoy!

Spartan Adam-D014 was a lone wolf assigned to the UNSC Lightning. What was supposed to be a routine mission ended up with the frigate being ejected from slipspace unexpectedly, and with Adam landing on a strange planet inhabited by colorful, friendly equines. But something's not quite right... Adam's turning up in Equestria was more than mere coincidence, and Adam is determined to find out just what is going on.

Enjoy!

This story is a sequel to Mr. Disc

Once upon a time a retired art teacher, whose name is Mr. Disc, accidentally stumbled into a land of talking ponies called Equestria. He found out quickly that he was in a world where it was close to his own, where his boss was a Princess, some of his students were ponies and even met himself as a spirit of chaos... After a while, he returns home to find that he was able to keep his powers where he lived happily ever after.

Well... not quite yet.

A huge thank you to SecretBrony01 for proofreading this story.

Finally, after years of begging, Celestia gives Twilight permission to access the Forbidden Wing of the Royal Library, a wing so secret even the other princesses can't access it. Twilight rushes to Canterlot, excited for the research potential.

Then she finds those books…

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The ever-helpful Twilight Sparkle sets out to design a compound to help increase brain activity in those who have a willingness to learn, but have trouble grasping difficult concepts. After acquiring a test subject in Rainbow Dash, the results are indisputable! Rainbow grasps new ideas and theories faster and more completely than ever before! But, how smart is too smart?

A diplomatic crisis arises between Equestria and the small, poor kingdom of Tarandroland, ancestral home of the reindeer. Celestia and Luna agree that it is time Luna takes a more active hand in foreign relations again, and Luna brings Twilight with her as someone she actually trusts and can talk to. But the mission turns out to be much more than political discussions - if scheming unicorn courtiers, unfriendly surly reindeer, bloodthirsty pirates, ancient sorcery and dangerous monsters weren't enough, our heroines must deal with something old - older than Luna. And is Luna really ready for diplomatic action, will Twilight learn to use a fan properly, and exactly how wrong are Spike's superhero comics about reindeer mythology?

Now has a TV tropes page

With the Equestrian Girls movies out, taken place in a universe that everypony from Equestria is in human form, I've decided to do a thought experiment.

The following story has to do with their version of Discord (simply known as Mr. Disc), and what would happen if he had stumbled into the land of Equestria.

A huge thank you to his Highness PrinceCelestia for making the cover art.

Edited by ginger468 and SecretBrony01

In the wake of the interrupted wedding of Princess Cadence and Shining Armor, the Royal Guard went on a changeling hunt, fanning out throughout Equestria to find any changelings living amongst ponykind. The captured changelings have been confined to a guard barracks in Canterlot.

Meanwhile Princess Celestia is finding herself swamped with petitions from ponies across Equestria asking for amnesty for their changeling friends, colleagues, and lovers. Princess Luna, who has been itching to regain some responsibility since her return, offers to take on the petitioners... and the changelings.

(sex tag for off-screen births and hinted baby-making)

For Sweetie Belle, having a babysitter is not that big a problem, especially when her babysitter is the element of magic herself. When Twilight devises a spell to help her with her apparent problems, however, both of them will have to learn a lesson that won't soon be forgotten.

Now has a sequel called Sizable Differences

Enjoy.