It shouldn't have been a big deal. Celestia was kidnapped or knocked out or just generally made to seem powerless by whatever idiot with ill intent decided to show up on a nearly weekly basis. As the mighty and immortal Sun Princess, she could escape at any time, but she was happy to play these little games. The daring rescues and bloodless battles gave her ponies such a sense of confidence and purpose!
But this one didn't go as planned. One small, stupid mistake got her thrown to the twisted reaches of the world-prison, Tartarus. Now alone, unarmed, and barely more than mortal, Celestia wakes in a living landscape where everything has every reason to hate her.
And, far worse, she has accidentally picked up a passenger.

Sidenote: This a repost (I tried to go through official channels, I promise!) of a story I wrote long, long ago on an account I foolishly deleted. Back in those days, Tartarus hadn't shown up in an actual episode yet. It's not exactly an alternate universe situation, but it has nothing to do with the canon portrayal of the place.

Super amazing cover art by Cold In Gardez.

Celestia has always wondered why Twilight never replied to most of her letters. Fortunately Luna breaks the news 'gently'.

A rather silly idea that popped into my head this afternoon. I make no apologies.

Edit: As a few people pointed out, the title was really giving the story away; I've changed it on their (sound!) advice.

This story is a sequel to The Fallen Age

Long ago, before the rise of Equestria, long before the Three Tribes Era even, Equus grew and prospered under the rule of the seemingly immortal Empress Cosmos. For two thousand years, she and her five Exarchs guided the many races of the world into a better future.

And then, she vanished, and her name and all she had done was forgotten.

Ten thousand years have passed since that night. Her Exarchs have not been seen in millennia, and the few who do know of that time think they died long ago.

The civilization she helped create is now forgotten by most, destroyed in a war born of xenophobia. One that heralded the rise of the Three Tribes Era.

But now signs have begun to appear. A long-forgotten prophecy is about to be fulfilled. The once and future ruler of Equus is about to be reborn. But what does this have to do with Twilight Sparkle and the five new ponies who have just arrived in Ponyville?

Five hundred years have past since Celestia and Luna handed the reigns of rulership to Princess Twilight Sparkle. Five centuries of unprecedented peace and prosperity.

So it came as a surprise to the sisters when Princess Twilight requests their presence in Canterlot. But the biggest shock is her second request.

Twilight will be out of Equestria for some time on an important diplomatic mission, and she needs someponies to take over while she's away.

Seeing as how long they had once done so, Celestia and Luna agree to temporarily take back their old titles. It shouldn't be that hard to rule again.

Right?

After the twilight was betrayed and abandoned by her friend, BBBFF and her mentor. She was imprisoned by fake cadence in a crystal cave below the canterlot. While she was in despair, a voice called "Welcome ... Master".

This is my first time writing a story so it won't be very good, anyway thanks for watching.

Luna has always seen Celestia’s caring nature towards their subjects but to Twilight it was different. 

Equestria, a land of peace and prosperity. It has been free of any true war for centuries and has prospered for it. However, it has also changed little in that time and its guard isn't what it should be. For several centuries now House Star, a noble house that is the last standing member of the ancient Lunar Court, has tried to get Canterlot's other noble houses, and indeed the royal of the sun, to see this but have never succeeded. Twilight, newest princess of Equestria and heir of House Star, just might know a way to shake things up.

  The Cycle of Flame defines every phoenix’s life, even those who refuse to fly the path ordinated by the Cloudsong. One such mischievous phoenix has found a home on the edge of the dangerous Dragon Lands. But after an old friend beckons her home, this phoenix meets a creature of myth and legend who gives her a once-in-a-lifetime opportunity.
  The phoenixes know her as Glorious Dawn.
  But the ponies of Equestria know her by a different name...

Entry for EFNW Scribblefest 2017 - Prompt: Growing up wild and forever free

Featured on FimFiction on March 13-16, 2017 with a Hot Tag!

Historian's Note: Believe it or not, this is not set in the Wavelengths Timeline!

Cast: Philomena and Princess Celestia with the Dragon Nation and the Griffon Kingdom

Cover & Section Break Design by Novel Idea
Flame Icon by MisterAibo
Philomena by moongazeponies

Beta Reader & Editor Credits
Ebon Quill - Audio Director & Quest Designer on The Manehattan Project
Tchernobog - AppleDash Fanatic, Special Guest Beta Reader
Little Tinker - Master of Systems at Poniverse & Scripting Engineer on The Manehattan Project
Beltorn - Commenter-at-Large on FimFiction
Painted Heart - Wife of the Author

Word Count: 6,600
Version: 2.6

When Twilight returns Cerberus to Tartarus, the last thing she expects to find and happen is to meet the ruler of the realm herself.

Even less so when that pony, Penumbra, turns out to be an alicorn. As she spends more time with the mysterious mare, Twilight finds herself drawn to her.

Unable and unwilling to leave Penumbra alone, Twilight strikes a deal with her to allow her to leave Tartarus. A deal that will change both of their lives.

Over 5 centuries ago, halfway through Celestia's millennium long reign, a rebellious political faction attempts to take over Equestria and start a new pony republic. Celestia is accused of crimes against ponykind and put on trial in an effort to remove her from power. Celestia must defend herself, and her actions, against the conspirators who aim to take over her kingdom. The fate of friendship and the future of Equestria hangs in the balance.

Told through the perspective of Princess Twilight reading the story to Luster Dawn.

Cover art by Decoy the Skeletal Boy:
https://www.deviantart.com/theflamingalberto
https://twitter.com/skeletal_boy