Hi there, my name's Abel, I'm the new changeling on the block.
Been living in Ponyville for three years. Been here a year before Twilight and managed to make a name for myself as a darn good accountant that goes by the name of Balanced Books.
Even got along with each of the Bearers pretty well. Well enough that Twilight decided to invite me along for her brother's wedding.
Getting past that shield the first time wasn't fun. Figuring out the plot behind the wedding, also not fun.
Did I happen to mention that any and all changelings who are NOT a part of Chrysalis' Hive Mind have a VERY good reason to hate her? Me moreso than most?
Yeah, that was torture.
Now all I have to do is explain to the bucking princessess about my true nature and pray to, well, them, that I'll be allowed to return to my life as Books.
Wish me luck, my interrogator is here.
Cover art provided by jjamess10

MLP/Undertale crossover.
Not a PWNY-verse story.

Long ago, the Monsters and Humans fought a great war. The Monsters lost, and were sealed in the Underground. It would take the power of seven human souls to break the barrier that kept them imprisoned. They only had six. And so the Monsters waited and hoped, praying that another human would find their way to the Underground. Some thought the seventh soul would give their King the strength to break the barrier. Some dreamed of a human who would be their friend, and save them all...or had nightmares of one who would bring back the war.

...but nobody came.

...but somepony did.

Eons after the war, with no way to tell how much time had passed above, a tiny blue filly with wings and horn fell into the underground, calling for her Mama. None knew the poor creature's nature or origins...but her soul was powerful with magic, even more so than a human soul.

None can know what will come...of this little 'Woona'.

Cover art by Sanyo21

When Twilight Sparkle accidently drops a truth potion at one of Celestia's parties, chaos happens as the ponies learn that some things are best left unsaid!

Be Awed and Amazed by the tale of Sweetie Belle as she traverses the multiverse in search of her lost mentor and friend, Twilight Sparkle! Will she find her in post-apocalyptic Equestria? Or maybe in a strange world where everypony is the wrong gender? Or even where a Pony claims to be a human? Read as she journeys through very familiar worlds you might have read about... if you dare!

At this point in time all the main worlds to be visited have already been chosen. Thank you all for the suggestions, and I hope you enjoy the surprises!

Here's the official TSC:F Music Intro: The Sweetie Chronicles: Fragments

WDTP: S2/3-CE
You can also visit the TV Tropes Page which has spoilers!

EDIT! This series is now open universe! You want to make a spinoff version? You totally can! You want to self insert yourself into their shenanigans? You can do that too! The characters and story are now completely public domain. I've lost interest in the series but if for some reason you actually like it enough to write your own take on it, you're more than welcome to! I'd love to read them, so feel free to link back and please remember to credit me/the story as the source!

Thestrals were defeated by the Princesses Luna and Celestia a thousand years ago, and are thought extinct. But what will happen when one moves to Ponyville? Disguised as an earth pony, Acrylic does her best to fit in. The burden of hiding her wings weighs heavily on her, and keeps her from becoming truly close to anypony. Can she keep the secret, or will she expose her entire race?

Set only a week after the banishment of Princess Luna to the moon, the realm of Equestria is in a state of upheaval. Celestia's royal guard attempt to regain control over the vast empire once ruled by dual monarchs, and the young alicorn's actions as a ruler have become a subject of scrutiny after her sister's attempted coup. Two factions have risen in the turmoil: The Knights of the Sun and The Bright Moon.

Far away from the political infighting and sword rattling exists a small mining town on the outskirts of Equestrian territory. Where once the royal guard would have no trouble fending off raids from bandits or other criminals, the panic of the capitol has caused a withdrawal of military forces to more essential cities and trading ports. Completely undefended and without a spell or sword amongst them, this town was soon overrun by a band of bi-pedal canines calling themselves the Diamond Dogs. As brutal as they are lazy, the Diamond Dogs have forced the local population to work until collapse to collect gems from the town mine.

Outraged by his inability to fend off these bandits and thieves, a young unicorn named Bone Marrow tries with all of his might to find his purpose in life - his cutie mark - and hopes that it will be enough to drive off the invaders of his home. He will soon discover that his special talent is far more than he bargained for.

((A Sequel will begin for this story as soon as I finish I Am a Pet Changeling. Stay tuned on Discord! https://discord.gg/nDXd3AB ))

This story is a sequel to Princess Celestia The Changeling Queen: Stories Behind the Mask

At the Royal Wedding, Chrysalis and the Changelings were revealed to all of Equestria.

But another mask was torn away that day. A mask born for a thousand years. A mask created on one promise. A mask, that has become synonymous, fused, to its bearer.

A mask that when ripped off, causes Twilight, her friends and Luna to question everything they ever knew about the one pony, one very important pony.

At the Royal Wedding, the meaning of the phrase 'Princess Celestia' changes forever.

NOTE: Chrysalis is NOT Celestia!!! That'd be impossible to pull off.

Credits to: Plainoasis for the design of the cover art
Note 2: Original cover art here: https://angelea-phoenix.deviantart.com/art/Contest-entry-Changeling-Celestia-337023552

Pre-read/edited by Zervziel,
Blankscape,
FinalFan,
Courage Fire
Aurora Borealis

Side Stories to this can be found: here.

An audio-reading on youtube up to Chapter 21 is up by StraightToThePoint Studios. I'm aware there are others but this is the nearest complete one: [embed]https://youtu.be/X3eMW673CSY[/embed]

There are also 2 print versions of Princess Celestia:The Changeling Queen. Nonexistent Publications run and Ministry of Image's run.

Contribute to the TV Tropes Page (thanks to Babs_Seed72 for getting it up)

After a tragic accident, a human ends up in Lord Tirek's body, as part of an attempt to reform the villain after his recent escapades. While the hero of our tale is trying to make sense of his new surroundings, the rest of Equestria thinks that the most terrible threat that their world has ever seen is back...
And the powers that be are definitely not happy about it.
New Cover Art By Shadow Bolt

When Princess Celestia is taken from her world to a planet of humans, she is immediately housed by a human named Alex. Promising to take care of her until a certain portal would open, he only asks her to stay in the house until then. Celestia however doesn't completely trust this alien creature and his sudden hospitality. She wants more than words before she'll listen to him.

Celestia said it herself, that Twilight Sparkle is no longer her student. While wandering around in the city of Canterlot one day, Her Highness stumbles upon Trixie's local stage show. To Her Highness, there seemed to be much potential behind the mere performer's act, and soon found it hard to resist taking Trixie under her wing.

Would Trixie even be up to the challenge?

Slightly edited by NemoSpecific.