After a magical accident, Celestia and Luna must try to restore harmony. Celestia's duplicate, however, is having none of it.

Check out the companion pieces, Amphelion, by monokeras and The Banach-Tarski Dragon by CCC, tackling the same premise in a different way.

Cover art from the gallery of mysticalpha.

A 'Human in Equestria' story, but reversed.
And by that, I do not mean 'a pony in the human world'.
A human is in Equestria Equestria is in a human!

A quick one-shot. Hopefully it will entertain you a little.
It could have been made longer and more involved, but there wouldn't be much point to that.

Chinese Translation by forgivenlove

Applebloom just wanted to spend a day with her friends, crusading for her cutie mark. Instead, she found something even deeper and more troubling about herself. Turns out she's not even a member of the Apple Family by blood. In fact, she's not even truly native to Equestria! She's an alien! An alien robot no less!

Now Applebloom will have to deal with the reality of her origins and try to cope with them and her newfound abilities as she moves towards her future; a future that just might never come to be if her new foes have anything to say about it. Decepticons are, after all, a monstrous cabal.

Now, it's up to Applebloom to light Equestria's darkest hour.

Cover image credit goes to Inspectornills

This story is a sequel to A Stitch in Time

Having discovered the message left for her by Star Swirl the Bearded in the distant past, Twilight once again finds herself caught up in the middle of a struggle against forces far greater than herself. In order to even stand a chance she'll need to travel further and wider than she ever has, and forge some unlikely alliances with old enemies. All to bring down the powers that have manipulated and shaped her entire life, and retake control of her own future.

The conclusion of the Time Loop Trilogy, which began with Hard Reset
Available in Spanish thanks to dgs1993
Series TV Tropes page

*Set in the Equestria Divided universe created by PoorYorickDA*

Nighthooves under the service of House Whitegold found a diary in the aftermath of a Zebra and Everfree incursion against an Earthborn outpost near the southern edge of the Everfree Forest. While it was determined that the diary held little information of value to the House, the pony who discovered it found its contents interesting.

Said contents are detailed below.

Shocking, how Celestia never taught Cadance the Royal Canterlot Voice. And Twilight will need to learn it as well. What can a Princess of the Night do but hold a class to teach this essential art for princesses? Hopefully she knows how to maintain classroom discipline....

Cover by Guardian Core.

This story is a sequel to Hard Reset

After the events of Hard Reset Twilight's life and mental well being are slowly returning to normal. Her recovery is cut short, though, when a letter arrives informing her that the time loop spell she cast is causing severe damage to space and time itself. In over her head, Twilight tries to summon anypony who will know how to fix it. The pony she gets is the last one she ever thought she would meet... and nothing like she expected him to be.

Available in Spanish thanks to dgs1993
Series TV Tropes page

Twilight isn't having a very good day. An experimental spell blew up in her face, an army of changelings is attacking Canterlot, and she just died. Yet somehow, it looks like it's going to keep going downhill from here.

Given the chance to correct what's gone wrong, Twilight swears she's going to fix all this even if it kills her. Which it will. Frequently.

Cover art by Pixel Prism
Spanish Translation
Series TV Tropes page

In a world full of magic, mere words can pose a deadly threat. When simply reading a sign can instantly infect the unwary, and cases start to turn up all around Ponyville, Twilight Sparkle casts the only spell she can find that can give her the time she needs to find the cause of the plague. But then she has to figure out how to stop the epidemic... without being able to read.

Editing provided by Spabble
If you like this, try Rainbow Typhoon
Audiobook on YouTube and for download on SoundCloud
Spanish version translated by MIkimoco
Russian version

The storm is breaking on the Horizon.

It's been two months since the battle against Nightmare Moon. Luna is recovering, Celestia is busy turning the government back into a diarchy, and the Mane Six have returned to their lives. All seems well, but when Celestia discovers that half of the power of the Elements of Harmony have been transferred to each of the Bearers, she decides to send thirteen mysterious members of the Royal Guard to monitor them as they manifest and develop their new abilities.

The sins of a forgotten war still linger, and an ancient evil lurks in the shadows, just waiting for the right time to strike. The Mane Six suddenly find themselves once again at the heart of a conspiracy to bring about Eternal Night, and only by awakening their powers and realizing their full potential can they do anything to stop it. Friends both old and new will help them along the way, and an unseen force will guide them as it seeks to right a wrong made thousands of years ago. The Bearer's journeys will take them outside the borders of Equestria and into the world beyond, and when they return, they'll have the power and experience necessary to save the world and bring about balance in all things.

The Powers of Harmony TV Tropes Page (SPOILERS)
The Powers of Harmony Art

Thanks to Wildy71090 for the cover pic.