The royal court of Canterlot welcomes its newest member with open forelegs: the human philosopher Voltaire, from Earth.

On Earth, Voltaire is known as the greatest enemy of tyranny in the history of literature, and a legend in his own mind.

On Equestria, the court betting pool is giving him a week before the Princess banishes him to the Moon.

Note: This story doesn't have sequels per se, but there are a couple of short follow-ups set in the present day ("Parade Coverage" and "Secret Histories"), and a prequel of sorts in "At the Inn of the Prancing Pony".

TV Tropes page.

In the dark,six voices dwindle. They drift, forgetting life and love and hope, eaten away by time and void.

And then, suddenly, there was colour.

It has been ten years since the defeat of the Changling Queen, and Equestria is again at peace. Twilight Sparkle and the Elements of Harmony have reached their prime, and have begun to settle down. Love and life abound in Ponyville, especially for Twilight's friends, but she has nopony to call her own.

There is a reason.

A series of events lead to a horrible revelation, and Twilight is thrust deep into a terrifying web of secrets and lies. Her peace is over.

This time, however, she won't be fighting monsters or madponies. What she faces will be much, much worse.

Act One of Two.

Act Two is here.

Currently undergoing editing by the wonderful Mstar!

Chrysalis is dying, and with her, the last of the Changeling race... but there might be a way to avoid extinction.

Ponyville has never been a stranger to interesting events. But, when an unknown species, a human, shows up out of nowhere early one evening, things begin to take an unusual turn. Is his appearance just a coincidence, or is there more to him than anypony realizes?

Check out its sequel The Blessing and the Curse!

The sun has set and risen many times after the changeling's attack at the royal wedding. Even as months past and the wounds left to Canterlot begin to mend, scars remain, perhaps unable to heal...
Such scars riddle the changeling queen, scars from a past that nopony alive remembers, save Celestia. Visiting Celestia in the middle of the night, she taints the air with a threat, or perhaps a promise?
Celestia contacts the bearers, requesting that they come to canterlot in case it needs more defense then Shining Armor and the guard can give, only to here something disturbing.

Twilight is gone, tearing away the greatest weapon they have.

Featured Twice, I'm not sure of the first date, but also on 1/13/15

Majesty Song has always loved the statue garden. One night, while she sneaks into the garden as a young mare and meets Celestia, she begins her lifelong path to discover the dark truth about the statue garden's creation and purpose and her own purpose in a family that pushes her to be something.

A short story with help from magnumopai. This story begins over 900 years after the banishment of Nightmare Moon and takes place over the space of 15 years.

Ever since Bon-Bon left for a new life in Manehatten, Lyra's life has lost its focus. She gets up, she goes to work, she eats, she goes to sleep. One day she knows she's going build up the courage to tell Bon-Bon how she really feels about her and they can live happily ever after.

That day will never come. Something terrible is happening in Equestria. Something that could be the end of the world. The Smooze has arrived and no-one can stop it, not even Twilight Sparkle. What hope then does Lyra have?

Windfall takes place seven years after FiM's main timeline. The Elements of Harmony have gone their separate ways, but are still close, and all the girls come running to be there on the eve of Fluttershy bringing her first foal with Big Macintosh into the world.

If you enjoyed this story and this fanfiction future extrapolation, please consider reading the sequel Earth & Sky

Twilight's relentless study of Pinkie's strange abilities leads to a horrifying revelation.

This site really needs an existential horror tag.