Twilight decides to go out for a friendly night of drinking with her two friends, Pinkie Pie and Fluttershy, to relieve the stress of planning her brother's wedding and defending Canterlot against the changeling invasion, but not all is as it seems.

A letter arrives in the middle of the night, informing the unicorn that one of her two friends has been replaced by a changeling.

What would you do if you've gone where no mare has gone before, and have no idea how to get back?

Rainbow Dash found herself alone in a strange, magicless world governed by entirely different natural laws than Equestria, ruled by a race who thought themselves the only sentient species in the universe...

Canterlot... For centuries, Canterlot was the shining gem of Equestria, the pinnacle of pony society. Now, it’s a reminder, a bleak and monolithic warning to the world. 

Changed by the chemical and technological poisons that plague the mountain, an abomination of nature, I wander the greatest disaster Equestria has ever seen. 

... I will escape eventually, and when I do, I hope my friends still see me as Twilight Sparkle, and not the monster that hides among the ruins. 

Mood Wings - Observations on Pegasus Body Language.

When Twilight Sparkle finds this book, she discovers an entirely new field of research. The secrets of pegasus wings lie before her, and she insists on making her own observations on the matter.

How?

Field research, of course.

The unthinkable has happened. A new Draconequus has emerged, apparently intent on plunging Equestria into chaos once more. To make matters worse, Pinkie Pie is nowhere to be found, forcing Twilight and the others to scramble to find a way to defeat this new threat without the Elements of Harmony.

Meanwhile...

After strange dreams, Pinkie Pie awakes and finds herself in the body of a Draconequus. Between strange new powers that she can't control, and, for some reason, an inability to communicate with other ponies, Pinkie finds herself alienated from her friends... but finds help from an unexpected source.

To Holmes, she was always "the mare." Whether she stole the Starry Night was perhaps beside the point. What mattered to Holmes was that he had been matched at his own game, by a mare; that it had not been altogether unpleasant; and that she had caused him, however briefly, to turn his keen and unflinching gaze upon himself.

On EQD July 31, 2012.

Lyra knows the truth. Lyra knows that a shadowy conspiracy dating back to the very dawn of Equestria is responsible for manipulating every major event for the past two thousand years. And Lyra does not care how many museums she has to destroy or how many transdimensional rifts she has to open in her quest to inform the public.

Now with cover image by Madmax! http://img215.imageshack.us/img215/3595/theyaretheworst.png
Spanish translation: https://www.deviantart.com/spaniard-kiwi/art/No-servir-a-estos-ponis-999961442

Audiobook: https://youtu.be/W8W0xxVHtmI

Hippophobia: An abnormal and persistent fear of horses. Sufferers of this fear experience undue anxiety even when a horse is known to be gentle and well trained. They usually avoid horses entirely rather than risk being kicked, bitten or thrown. They may also fear other hoofed animals such as donkeys, zebras, mules and... ponies.

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

It is the year 2038, and the Earth is slowly being consumed by a space-borne monstrosity dubbed the Black Tide, which is using nanotechnology to remake the planet into something hideously alien.

Erin Olsen works for Project Harmonics, humanity's last-ditch effort to find a new world before the Tide can wipe them out. But when that world is found, and it turns out to be occupied, Erin will need to find the courage to face the unknown in order to save the inhabitants of both worlds.

(Many thanks to Easteu for the fantastic cover image for this story!)

Now with its own TV Tropes page

There is now a follow-up to this story: Sunflower - Side Projects
Sequel: Project Sunflower: Harmony