It occurred one peaceful night. Half of Equestria awoke to the sound like a double-shot thunderclap. A percussion heard in the skies and rattling windows from Apploosa, to Canterlot, to Ponyville. Nopony knew what it was or what it heralded for the world as it drew a line across the nation.

For Twilight Sparkle, this isolated incident might have faded from memory after a time, if not for the strange rumors of a creature sitting on the hill on the outskirts of town.

These are her thoughts given written form. These are Sparkle's Notes.

Report EVERYTHING to the Princess.

The Cutie Mark Crusaders have always lived in the now, getting what they think needs to be done as a soon as possible, executing their plans just so they can move on to the next one right away, not thinking about the consequences till they’re right there in their faces. But when an attempt to earn their cutie marks goes too far, Sweetie Belle and her friends must face a horrible reality that sends their world into darkness and fear. How will the truth be uncovered and what will be sacrificed to undo this nightmare?

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. 

Having failed to reach Davy Jones' Locker with the rest of his crew, Captain Hector Barbossa finds himself stranded within a hell many times more terrifying; a land infested with magical talking horses and little baby dragons. Despite the odds being stacked against him and the inhabitants of Ponyville at his back every step of the way, he vows to return to his own world and finish the quest he started.

If only fate did not have a new adventure in store for him. An adventure that could very well change the fate of Equestria and the Caribbean seas forever...

Twilight Sparkle wakes up one morning to a harsh dose of unreality. She is stranded, without her friends, on an island which matches no known locale on Equestria. Surrounded and harried on all sides by the alien and the dangerous, she will find her mettle sorely tested, and find perhaps that the best friends you will ever have in your life are the ones you make when your back is to the wall...

Thanks to CedricBale and noobie56xx for tracking down the name of the artist so I could give them credit.

In the wake of the events of "Infernal Machines" and the Nightmare's most pathetic assault on Ponyville yet, Applejack is thrown into an existential crisis, despite her not knowing what the word "existential" means. So when a stranger named Stranger arrives in town, teaching a new way of coupling talent to power using complex machinery, she is quickly suckered in, along with everypony else. Now, it falls to the Most Dependable of Ponies to bring the resulting ruckus down to earth, but can even Applejack's legendary pragmatism stand up to the brain-fizzing horror that is... CONTRAPTIONOLOGY?

Now with a Spanish translation by Spaniard Kiwi!

The star system Omega Centauri was just another oddity on a map to scientists in the not too distant future. However when they found the star was orbiting an earth-sized, earth-like planet instead of a black hole as its motion had suggested, a mission was scrambled to investigate this most unusual of celestial behaviors.

Hamstrung by politics, and nearly crippled before it began, the 'Lone Ranger' mission was reduced to just one crew member and left to his own devices.

These are the logs of Arrow 18 and its lone commander. This information is classified TOP SECRET by the Global Space Agency.

Do NOT tell the princess.

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?

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 is a story about a journey across time, space, and some other strange dimensions that I don't have time to go into right now. It is a story of six... no, wait, eleven... no, it's... it's a story about quite a lot of ponies, let's put it that way. It is a story about those ponies, and the trials they face, the friendships they form, the pumpkins they ignore for no discernible reason. It is a story of betrayal, of hope, and all the cliché things that really good stories are made of. But for now, it is none of that. As far as we are concerned, this is a story about a young filly and her friends, and a game they play together...

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Author's Note: Hey everypony! This is my first fic (or at least, the first fic I've ever submitted) so please rate and comment telling me what I could do better!

Just to clarify, this is a MLP / Homestuck crossover. There will be OCs, there will be lazily imported Homestuck mechanics, but hopefully there will also be entertainment to be had.