Cheerilee is becoming frazzled after a long semester. But when a friend recommends a new dance club in Ponyville, she feels she's too old to partake in today's current hip scene... or is she?

What would you do, if you met a pony who was at once your brother, and yet not? Applebuck wishes to reunite with his 'Cousin JayJay', and braves the dimensional divide to reach his goal. But being a small foal, how will he deal with a world in which everything is flipped? His friends, his family, and even... himself?

Twilight and her five friends are transported during a botched spell, across dimensions to... Ponyville, Equestria? But not the same one that they knew. Sitting on a bench is Harpsy and Babar. The Doctoress avoids apples from an aspiring Applebuck. And in a library across town, six stallions join their forces as they try to decipher the appearance of filly look-alikes of themselves around Ponyville!

Rainbow Dash attends her hometown's Millennial Summer Sun Celebration, where she meets a peculiar pink pony. When a strange portal appears during the testing of Twilight Sparkle's latest invention, and pulls their new companion inside, the two friends give chase and embark on the most important adventure in all of history.

Equestria Daily | TVTropes

This story is a sequel to A Stitch in Time

Having discovered the message left for her by Star Swirl the Bearded in the distant past, Twilight once again finds herself caught up in the middle of a struggle against forces far greater than herself. In order to even stand a chance she'll need to travel further and wider than she ever has, and forge some unlikely alliances with old enemies. All to bring down the powers that have manipulated and shaped her entire life, and retake control of her own future.

The conclusion of the Time Loop Trilogy, which began with Hard Reset
Available in Spanish thanks to dgs1993
Series TV Tropes page

What was originally meant to be a single piece, this story, its prequels and sequels, focus on the mane six and their dealing with being the Elements of Harmony, how ever long that will last...

When dark creatures begin appearing in Equestria, Princess Celestia and Princess Luna summon the bearers of the Elements of Harmony to Canterlot. Before the six ponies can arrive, though, four strange ponies are expelled from a portal that appears in the throne room, and they explain that Equestria is not the only place at risk from these creatures. Thus begins an adventure that will reveal a greater destiny for Ponyville's librarian than she could have ever dreamed of.

Kingdom Hearts/My Little Pony: Friendship is Magic crossover. Pairings undisclosed.

The Elements of Harmony are defeated and Nightmare Moon stands on Equestria's throne as their new Queen. Is Equestria doomed to suffer through night time eternal or will they be... perfectly fine? Twilight finds her new job as slave or "personal assistant" to her new ruler to be a bit maddening. But is this evil sarcastic queen really as bad as she originally believed? And just how many others are diabolical enough to cash in on the change in staff? Can Nightmare truly run a peaceful Equestria? Let me just answer all these questions right here in the description...

When Twilight Sparkle slipped beneath the covers last night, everything had been fine. She had friends whom she loved, a teacher she adored, and a bright future ahead of her. But when she woke up, her blankets and quilts had been replaced by hospital gowns and padded restraints.

Everything is wrong and nothing makes sense; even her friends have changed. The doctors keep telling her that she is sick, that none of it was real and that it was all in her head. Yet she remembers a life far beyond the hospital walls. She couldn't have made it all up on her own. They must be lying… right?

Ask Asylum Twilight - Still updating regularly!
Equestria Daily
TVTropes
Asylum Fan Group
The Tartarus Project
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The Asylum 20,000 View Spectacular Stage Show!

Art:
Asylum Cover by conicer
Twilight and Twilight Smiles by dreamingnoctis
Mirror Twilight and Plague Doctor by Jaestring / BloodGoldWings
Twilight Smiles and Doctor AJ by conicer
Nurse Ratchet and Silas and What's in the mirror? by Archonix
Doctor AJ Sketch by Archonix | Colored and vectored version by ReFro82
Twilight's Asylum by Khan the Cake Lover
Smilight by HappySwitch
Twilight Waking Up by Dombrus
Fan Art by toxicdemon10
Asylum Twilight by Madness-With-Reason
Asylum Fluttershy and Asylum Ch 26 by Downburst-Backspace
Twilight and her Twin by v747
Birdgirl by sirValter

Readings and Videos:
Asylum Animated Trailer Video by formuladash
Reading by Gammarobot (SugarCubeRadio): All Chapters Here
Reading by Ender Brony: All Chapters Here
Reading by VisualPony: All Chapters Here
Reading by MelancholyIguana: All Chapters Here
Fan Trailer by Kaidan: Asylum FanFic Trailer Cuckoo's Nest

Sanctuary by Kaidan
Broadhoof Files: Dr. Humors by TypewriterError
Broadhoof Files: Corporal Phalanx Spear (Ret.) by Phalanx Spear
A Hearth's Warming Tragedy by Seven Fates

A special thanks to Breath of Plagues, Rex Ivan,
ChudoJogurt, Cynewulf, Death the Kid, Selbi, PrinceDolph, Blahman2816, Queue, and Gage!

Axan Zenith - Dr. Dreamer
Dratini4 - Way Finder
psychicscubadiver - Bright Mind
Velkaden - Dream Chaser
Reese - Silver Glow
Viola Heartstrings - Clover
Archonix - Spinney Whiteacre

Equestria is growing, and magical savant Twilight Sparkle is disgusted by the crime and corruption this change has brought. Her life is changed forever when she discovers the Death Note, a notebook with inexplicable and deadly powers. She uses this book to pass judgement on those she deems unworthy of life, aiming to create a perfect world free of crime. But when the two Princesses put their best pony on the case, a mysterious detective known only as L, a psychological game of cat and mouse erupts between the two.
Comments contain spoilers. Artwork by blu-red, opening by Anon3mous. Now with its own TV Tropes page.