Something has happened and Twilight finds herself in a strange and dark new world. The Bipeds here have strange magic, advanced technology, and a lot of problems. She needs a few friends, and they just might need her. WORM crossover. Deadpan29 has created some great supplementary material that is canon to the story.

After a failed attempt to help a friend, part of Twilight's consciousness finds itself exploring the Dreamlands, a strange and impossible world created from the dreams of every living thing in the universe.

Naturally, she keeps research notes.

It is a dark time for Equestria. Rumours are circulating about conflict forming between the Princesses, rumours which soon turn out to be true when the moon doesn't set one day. It quickly becomes apparent that one Princess has turned on the other, but no one is sure who has done what, or who the enemy is.

Panic occurs quickly, sides are swiftly taken and loyalties are questioned as ponies start to take up arms against one another in support of their chosen ruler.

Now ponies loyal to Celestia and Luna are ready to charge at one another, some out of loyalty, some out of bravery, and some because it's what they were told to do. Right now they are just waiting, since neither particularly wants to make the first move.

This is not an action story! Much more of a calm before the storm sort of thing.
From the p.o.v. of a nameless pony. Contains profanity.

Hanna, the CEO of Hofvarpnir Studios, just won the contract to write the official My Little Pony MMO. Hanna has built an A.I. Princess Celestia and given her one basic drive: to satisfy everybody's values through friendship and ponies. Princess Celestia will satisfy your values through friendship and ponies, and it will be completely consensual.

Rainbow Dash's latest flying routine was interrupted by a sudden mountain, and Twilight can hardly sleep at night. No pony should be this excited to play with necromancy.

Edited by Deceased and JustAnotherTimeLord.

Cover art courtesy of pony-berserker.

Dramatic reading by WritingStylus

Polish translation by atom2004
Spanish translation by Spaniard Kiwi
Russian translation by NovemberDragon

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

This story is a sequel to Project: Sunflower

After the events of Project: Sunflower, Erin Olsen has returned to Ponyville, happy to pursue her studies in magic. After everything that happened the year before, she's looking forward to spending her days studying and having fun with her friends.

Meanwhile, on the newly discovered world of Harmony, humans and ponies work together to study this strange new world. However, their arrival causes something ancient to begin stirring. Something that may end up changing everything.

Erin will need all of her courage, all of her cleverness and, of course, all of her friends to see herself through what happens next.

Cover art by Valkyrie-Girl
Editing provided by:
Brilliant Point, Coandco, Ekevoo, Ludicrous Lycan, Merlos the Mad and Razalon the Lizardman.

After Celestia's School For Gifted Unicorns runs out of repair money and none can be found in Equestria's budget, Luna invents a means to raise the funds. Now if she can just keep it from destroying the nation's economy...

(Part of the Triptych Continuum, which has its own TVTropes page and FIMFiction group. New members and trope edits welcome.)

Now with author Patreon and Ko-Fi pages.

Twilight Sparkle's Harmony Project is the culmination of her life's work. The only thing left is for everyone to be gathered, so that all of Equestria can join together in Harmony.

But now that success is staring her in the face, Twilight begins to have doubts. Fortunately, she has a friend like Discord, who is only too happy to lend a paw to a friend in need...

Editing work courtesy of NorsePony.

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

This site really needs an existential horror tag.