Hello, my name is Twilight Sparkle. My brothers are Shining Armor, captain of the Royal Guard, and a dragon named Spike that I hatched when I was little. I have five friends that help me wield the Elements of Harmony, artifacts that protect Equestria from evil. I have a few other friends that are less important, but still great ponies nonetheless.

One catch, though. I am also a changeling Queen, and the friends and family I just mentioned are all my subjects, and children as well. They don't even know it, but everything's working out alright, so no reason to tell them! After all, it's not like a giant wave of love energy could suddenly reveal all the changelings in Canterlot, right? Right?

Part 1, Revelation: Twilight Sparkle meets an old enemy that reveals a secret she's kept since she was named.

Part 2, Recollection: The Elements of Harmony try to get to the truth of the matter, changeling Queens begin their game of chess, Queen Citlali takes her Hive and runs from Canterlot.

Part 3, Reformation: Queen Citlali begins to grow her hive, Whitetail Hive takes some time to get used to the news, Princess Cadance dreams of a dark creature.

May 11-15, 2017: Featured for the maximum time... whoa.

Twilight has always felt just a little uneasy about how others treat her, but after a tragedy befalls the Sparkle household, she reveals her greatest truth at the funeral.

Can her friends, family, and teacher comfort her this time?

No. 

...but when emotions are high and mistrust and confusion are rampant, is everything what it first appears?

This story is a sequel to Twilight's Dollhouse

Thirty ponies remained trapped in plastic shells as Twilight’s dolls. Lyra left them behind without a second thought. She joins Scootaloo to help rescue them, lest they be trapped for eternity as the last of Twilight’s sanity slips away. . .

Scootaloo will have to get past thoughts of revenge and her anger. Lyra will have to move past her guilt of failure. Once they have learned the skills they will need to defend themselves they will set out to find the Dollhouse and rescue their friends.

Unfortunately, time waits for no pony.

Pre-readers / Editors: Selbi, Abcron, Jaestring, TypewriterError, Breath of Plagues

The newly coronated Princess Twilight suffers an abrupt tragedy. Having lost two loved ones, she begins to question her own mortality, and that of her friends.

AJ, Dash, Rarity, Pinkie, Fluttershy. . . they are just the beginning. Twilight will live for thousands of years, so every pony she cares about—every pony she will ever care about, will die.

She could barely handle the pain of one funeral, let alone the thought of hundreds of them. Twilight finds a clever way to ensure all of her friends never die. They can’t all be ageless alicorns, but they can all move into Twilight’s Dollhouse. Then they can be best friends forever.

Sequel: Twilight's Dollhouse 2
Fanmade Song: Twilight's Dollhouse

Source: Dreampaw
Editor: Gage of Grandiloquence, Breath of Plagues
Pre-read & Idea pony: TypeWriterError,
v1.1 Revised chapters 1-10 on May 1st 2013
--Pending a few more revisions, including ch. 14
Now on TV Tropes.

Twilight was practicing a spell with Starlight glimmer, only to have starlight turn the mane 6 to foals and then get transported to celestia's castle. Now Luna and Celestia have to take care of them until they find ponies willing to adopt the mane 6. Who will adopt the mane 6? Or will they choose they're own parents/family instead?

This story takes place during the Season Five finale, "The Cutie Re-Mark". As such, there are spoilers ahead.

Starlight Glimmer's plan is working. All she has to do is upset Rainbow Dash's rainboom-creating race in the past, and Twilight Sparkle's connection with her friends will be severed. And she's done it. Repeatedly. Sure, Twilight can go back in time to try and stop her, but Starlight will always be brought back as well. No matter what Twilight tries, no matter how many times she returns, she can't stop Starlight. They're evenly-matched, and it's much easier to disrupt events than it is to preserve them.

That means Starlight wins, right?

Trixie is tired of being the cast-off and the laughing stock of Equestria. When she gets her hooves on a rare spell, she finally has the means to seek her revenge on Princess Twilight. Switching their bodies, Trixie becomes an overbearing royal overlord who wants everything her way. In the meantime, Twilight is stuck in Trixie's body and the Mane 6 have all been scrambled. Twilight and her friends have to find the answers to this puzzling spell before Trixie ruins Equestria for everypony!

This story is a sequel to Celestia's Tiny Student

(Title changed from "Ponyville's Tiny Librarian" for reason pointed in this blog )

Twilight Sparkle is a one-kilogram pony the size of a large rat, shrunken by Princess Celestia following her entrance exam to the Celestia’s School for Gifted Unicorns to ensure that her power surges would not pose a danger to the ponies around her.

She’s spent thirteen years full of hard training at her new size, facing the life-threatening experiences that came with living in a world of giants. To survive those thirteen years of hardship and joy, of learning and adventure, and of pride and humility, Twilight has challenged herself to be stronger, to overcome any obstacle.

Now that tiny Twilight is on her way to Ponyville to oversee the preparations for the Summer Sun Celebration, how well will this miniature mare fare outside of the confines of the castle? How will the other Element Bearers react to her? How will Nightmare Moon react to the tiny unicorn? Is Twiny prepared to face Ponyville, and, more importantly, is Ponyville prepared to face her?

Credits:
Art cover - kc day

Top editors: (editing and rewritting for months, hope quality is to your liking).
Kydois
Georg

Nightmare Moon's sentences editor:
Bahatumay

Applejack accent editor:
Crimson Star (Chapter 1 - Applejack)
Rebel Brony
The Notebook is grounded

Pinkie sentence's editor:
Plump it UP

Other editors:
Hereward
tana1100
Lab (small editing from prologue to chapter 4)

Pre-reader:
Rated Ponystar

To celebrate the release of this sequel, I created a group called “Twinyverse” for all fans of this story where you can talk about it and track all side stories with ease.
The Twinyverse Group

Twilight Sparkle never was a Unicorn and she didn't even know it.
What happens when her true heritage comes to light? Will she willingly embrace it? Or will she be forced to?

Beware of spoilers in the comments!

Edited by uTTerAbsurdity, Zervziel, Stormwatch and Gwenio

Cover art by the talented Cartoonlion and colored by the equally talented Stormwatch, original can be found here

Click here for the Tvtropes page

One cold autumn night, Twilight Sparkle lets in a pale and weary traveler into her home. When she accidentally discovers his dark secret, she is assaulted by him, and is left to die... When she woke up, she finds that she has been turned into a Vampire, an ancient enemy of Equestria last seen during Nightmare Moon's Rebellion. She now walks the thin line between life and death, sustained only by the blood of others.

Her friends now race against time to find a cure for this ancient curse, and stop the Vampire who infected Twilight, before he can create a new army of Vampires to conquer Equestria. Otherwise, Twilight will join the forces of evil and darkness, as the Bride for the Lord of Vampires. They have to work quickly, as every day passes, Twilight's thirst for her friends' blood increases...