One day like any other, Celestia receives a strange letter containing a unknown spell from Twilight. It sends her on a wild adventure with many twists and turns--for it sends her 20 years in the future! While in the future, Celestia discovers what her sister has gone through for over a thousand years, why Chrysalis saved her life, what has happened over the 20 years she has been gone, and what darkness stirs in the heart of Twilight Sparkle..
The true enemy, however, is soon revealed, and the lines are drawn. The question is not who wins, but rather, what is lost, and what sacrifices need to be made to get things right again.
Edit: Writers block so no story
Warnings:
1. There will be some language in this. not much, but some.
2. This will be long. Long as flip.

The world's going to end in one week. It's been doing that for a while now.

Someone in Equestria's broken the world. They've taken time along with it, trapping everything into a single, indefinitely repeating week. Only the elements' bearers move forwards in time, but they've got problems of their own. For each cycle drains their talents from them, each conversation twists old friends into enemies, and not a single one of them knows how to save the world. Some of them have even stopped trying.

And then Twilight finds a way. All that's left to do is gather everyone back together.

Story arcs written about an apocalypse cycling in perpetuity and the effect it has on Equestria. Not as dark as it tries to be.

Additional: Story formatted to look its best in Font Serif, Size Normal, Colour Medium-Dark, Paragraph Spacings 1.2; this as the banner image; no interactive pony, Snow Default, css color #8c8691, Background Pattern Stars and Background Image Night Town . Reading otherwise will expose you towards rogue spacings, silly typography and a severe lack of Luna.

Featured on EQD for crimes against humanity.

Pony Joe awakens before the dawn each morning, readies himself for his day, and then walks through Canterlot's cold and silent streets to his doughnut shop.

Life has become pretty mundane for Joe, but as he serves his customers and chats with his regulars he realizes that he has come to rely on that repetition...he relies on it to keep from remembering.

As a casual utterance by a new customer sends Joe into a spiral of haunting memories we learn about his life...and what he must give up if he wishes to move beyond his past.

Lyra stands alone under the tree where she met the love of her life.
With only a hoodie to shield her from the cold night she reminisces about the short time she spent with her love.

Beige is an exceedingly average mare save for just a few details; She's never found that special something that brings her the kind of joy other ponies seem to feel, and she's never gotten her cutie mark. After a particularly rough day, she might find what she's been looking for all this time. Will it be a dream come true, or the start of a nightmare?

On the eve of Twilight's wedding, trouble is brewing. Fluttershy mourns the love she lost and contemplates the bitter dregs of hate. Two friends loved the same stallion and he chose one. As mysterious murders rock the city of Canterlot and an ancient evil returns to battles long abandoned, Twilight and Fluttershy will finally have that peculiar heart to heart that only rivals in love can have.

Unrequited passion is a dangerous force. In normal circumstances, a controllable one. When two mares who loved the same pony are left alone in the dark? Perhaps a lethal one.

(EDITED by the Illustrious RazedRainbow, the better craftsman. )

This is the story of a young pegasus stallion, or you specifically. After the passing of your mother, and your ever increasing distant father, your brother has never felt safe in the cloud home. Afraid of heights and normal life in Cloudsdale, you decide to abandon your former life to start a new one on the ground, in a town called Ponyville. While there you find a cute mare that runs the local post office who goes by the name of Ditzy Doo.

She couldn't have made it herself. A solitary bookkeeper, long disillusioned with the "dream job" of maintaining the Canterlot archive, becomes the unwitting guide to a panicked Princess of the Night in the deepest recesses of their voluminous libraries.

Deep underneath the shelves and scroll racks, through the perilous and twisting caverns and gnarled trap-laden corridors, he realizes she isn't just seeking a getaway from the pedantic Canterlot politics. She's seeking to destroy an evil as old as the night sky itself. An evil that...well, she couldn't have made it herself...

The world spins, years pass, and everything comes to an end. Except Celestia. She sits on the shore of the last ocean, watching and waiting for her own chance at death. Because everything comes to an end if you wait long enough, and Celestia is patient indeed.

This is the story of how an entire fandom has overlooked one of the most popular character's true royal duty.

*EDIT* True duty as in why she raises the moon she is and forever will be the Princess of the Night

*Further EDIT* I am aware that there is nothing in canon to even suggest this other than physics not completely being ignored in Equestria and as such is a direction I hope the fanon will agree is a good one. This was written with the hopes of inspiring a new take on Luna stories.