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.

Driven by an intense Warp storm, a Rogue Trader vessel finds itself crippled and stranded above a world no human has ever visited. The natives are friendly; can the visitors say the same? A Warhammer 40k/Friendship is Magic crossover. Yes, really
(12/02 added epilogue to last chapter)

Eighty years after the events of The Dread Chitin, Equestria is a radically different place. The arcane science of the late Duran Thirk and the information found on the Star League library core have combined to catapult the nation's science ahead by hundreds of years.

Now, facing the possible aggression of a completely unknown alien power, Twilight Sparkle and her friends have to gather together once more, leading a crew of the best ponies they could assemble in a voyage outside their own star system. They seek to learn about their potential foe, to explore the galaxy around them, and possibly find allies and friends to stand alongside them. Who knows what they will actually find?

Stranded on a hostile, alien world, Twilight Sparkle and Rainbow Dash must depend on one another and a fellow alien castaway if they want to return home to Equestria.(originally published on FFN)

This story is a sequel to Together Forever

Twenty years after the events of Together Forever, Cadence still struggles to create a new form for her beloved husband as Shining Armor seeks the source of his wife's misery. Meanwhile, tensions mount in the world at large, drawing the intervention of Celestia. But is this all more than coincidence?

Now complete with a TV Tropes page!

A normal day was all it took.
A simple failed prototype, a missed experiment.
There was an explosion, and I woke up. I don't really know what happened between those two events, but I'm fairly certain I shouldn't have awoken in a small, dark box.

I'm scared.

Cover art by the amazing Avatar of Madness!

This story is a sequel to Three Goddesses, the Apple, and the Stallion

Cadence reads little Twilight legendary myths from before the time of Equestria.

A little collection of short stories to be added to when I choose.

Once, long ago, there lived three goddesses atop a mountain, ruling over ponykind in peace and harmony. Until one day, there came a spirit of chaos, bearing a certain gift...

Now featured on Equestria Daily!

Also enjoy a dramatic reading, by Goomba Brony.

[img]https://i.imgur.com/j8cG26r.png[/img]

Upon Nightmare Moon's return, the leaders of other nations gather to discuss the situation.

They're not especially happy about it.

Cover art from the gallery of WingFlyte.

Spanish translation, by SPANIARD-KIWI. Russian translation, by Dark Room Collaboration.

Hundreds of years have passed since the wedding of Princess Cadence and Shining Armor. As with all mortal life, Shining Armor was fated to die and his soul to pass from the world. But with magic, his end was averted. What price will his immortality demand?

Now 100% approved by Twilight's Library!

Featured on Equestria Daily!

Also on TV Tropes!

New cover art by the awesome BroDogz.