In the magical land of Equestria, two alicorn sisters raise the Sun and the Moon every day to give the world a night and day cycle, basic for the survival of life. There are also two alicorns who rule over two very core aspects of life and harmony itself. Those are Love and Friendship. While not as ancient as the two sisters, all princesses are essential to the world's balance.
This balance is also sustained by the hard-working ponies, who make the seasons change and manage the weather to fit their needs, so everypony has enough food and water, and every animal is also attended to assure that any of them are caught in the changes of seasons.

But what about the planet itself? What about Mother Nature?
This is the question that Gaia asks when she arrives to this foreign world. After so much work her son persuaded her to take a long vacation in Equestria, saying that she needed one and assuring her that he would be in charge now, and she must take a break. But what can a several billion-year old alicorn possibly do to pass her time in this land?

(SimEarth/MLP Crossover)
(Timelife of Gaia's life 'till the start of the story)

She was a unicorn on the run. Being hunted, her only option was to hide where they wouldn't think to look. Once over the border she'd hide in the most quiet, boring, unassuming town she could find in Equestria. Her information was out of date but how much could Ponyville have changed?

Once there all she'd have to do is keep her head down and not draw attention to herself. Certainly stay away from any adventure or authority figures, top of which being the Princesses. She'd shuddered to think what would happen if they found out who she really was. Still, what were the chances that she'd be dragged into an adventure or meeting any princesses while in Ponyville.

Thank you to 'Greynoise' and 'Starlight Nova' for editing and pre-reading respectively.

Having re-read the FAQ rules, now rated for Teenage-Gore.

100% Approved by Twilight's Library!

***WARNING*** Spoilers in comments

No idea who did cover art, let me know and I'll credit you.

(A PoE story.) Additional Tags: (Slice Of Life)
All Twilight wanted was to give Spike a special gift for his birthday. Yes, it was a book, but it was a very special book. An Enchanted Book like that Power Ponies comic they had recently experienced.
Things went wrong when Spike startled Twilight as she was working the spell for his (secret) gift. Needless to say, startling Twilight while she's in the middle of a spell can be a bad idea - as certain frogs can tell you.
Twilight has every reason to believe that she is now trapped in a closed reality bubble fabricated out of her own magic, with no way out. She's lost in some made-up universe reflecting some random story line.
Mike, of course, has a different opinion about the matter.

WARNING: Both Twilight and Mike love talking technical and explaining things to each other.

Twilight's World now has an audio reading by No One and Nobody. Listen HERE.

This most excellent cover art was provided by Void Heart

"Knowing all you've seen through that man's eyes, all his powers all but forced him to do... would you still strive to all but become him?"

Knowing what I know now, and what creepy sense that strange peddler's words now make to me...

I'd still say hell yes, of course. Come on. Magic. That's like the best thing that ever happened to me.

Becoming enemy number one of a country with demi-gods at the top just because my snark has gone into overdrive? Not so much.

For the League of Humans Acting Villainous group. Edited by Ranakastrasz, newbiedoodle, and Xanathar.

Will contain spoilers for the whole of The Dresden Files up to Cold Days, but can be read without knowledge of the series.

Thanks to the Dresden files wiki for making this easier and everybody that's made this bandwagon worth jumping onto.

The Princesses find an alien creature barely clinging to life at the scene of a terrifying crash. Can the Combined Power of the Elements of Harmony save it, or more importantly, should they save it? Will the arrival of this strange creature tear Equestria apart?

TV Tropes
https://tvtropes.org/pmwiki/pmwiki.php/FanFic/Article2

I used to be a human, but then I pissed off a wizard. Now I'm stuck in "Ponyville", in a land called "Equestria", and with no apparent way back home. I'm also pretty sure that I've just replaced somepony. I'd rather not have to answer any tricky questions, so I'm better off trying to be this unicorn whose name has been forced onto me.

My name is Twilight Sparkle, and I'm not a pony.

[Rated Teen for extensive use of vulgar language and sexual references.]

[Cover art made by richhap on deviant art. Unamused Twilight, go figure.]

[Brybrythesciguy is working on a cool audiobook of this story right HERE. The characters' voices are even simulated with an AI! I definitely recommend giving it a listen!]

So I went to bed as normal last night, dreading school and whatnot. Next thing I know, I'm a dragon, everyone is missing, and time seems to have gone on without me.

Now I have to find other survivors, figure out what exactly happened to the world, and battle with instincts that tell me to eat rocks and hunt every small thing that moves. It doesn't help that the others are ponies that run away from me when they see me.

Help. I need an adult.

Set in the Ponies After People universe, inspired by Starscribe's The Last Pony on Earth. Check it out, it's a great story and universe.

Awesome cover art done by Grammar404

Hidden Fortune and her sister grew up in the Wasteland, learning its dangers and doing their best to stay out of sight and out of mind of the larger world. During a treasure hunt they discover a Stable, and a chance encounter changes their world. Now the sisters must travel out of their element, learn how to survive all over again, and hopefully, discover the one true treasure of the Wasteland.

Cover art by Jordo76.

Twilight Sparkle has too much magic, and it will take her decades to learn to control it. Her spectacular loss of control during her entrance exam only proves that fact. She is a danger to herself and others.

After Sunset Shimmer’s disappearance, Princess Celestia needs a new student to bear The Element of Magic to defeat Nightmare Moon. With all of Equestria at stake, Twilight Sparkle…is not the pony she needs.

Princess Celestia seals Twilight Sparkle’s magic with the distant promise of one day teaching her.

But there are two diarchs of Equestria. Amidst a lucid dream, an offer is made.

“Hello, Twilight. Would you like to be my student?”

Cover art provided by Lafiir.

To be inserted into Equestria, it's a dream come true for anybrony!

Meet the ponies!

Have super awesome magical adventures!

Use foreknowledge to avoid all those silly pratfall moments without screwing things up and causing irreparable harm to the Mane 6...uh...hopefully!

And all for the low cost of possessing Princess Luna, denying her any real freedom or the ability to move on with her life since she's in your head and you're walking around as Nightmare Moon!

Yeah...there had to be a catch in there somewhere, didn't there?