This story is a sequel to Welcome the Unknown

Nearly a year and a half ago, Discord ripped Matt from Earth to Equestria to use him like a battery while he slumbered in stone, biding his time. When the two finally came together, the mere human managed to outwit the Spirit of Chaos and put an end to his short reign.

Several months have gone by since then, and all things considering, Matt has made a decent life for himself. He has friends, a home, activities to help pay the bills, the usual. But on one particularly average day, something he never imagined he'd ever see again appears and – whether he realizes it or not – threatens to throw everything out of balance. Too bad it's only the first in a series of things to come. What does it mean for Equestria? More importantly, what does it mean for Matt?

Rated Teen for some language and a couple suggestive themes. Reading the first part is recommended, but references to what happened will appear here and there as the story goes so that you should be able to piece things together in case you decide not to check it out. If you do, I hope you enjoy it!

Cover art credited to IJAB. Go say hello!

When Twilight discovers that Diamond Tiara's tiara is an evil magical artifact that turns the wearer evil, she promptly has it destroyed, curing Diamond Tiara of her cruel ways. Now, confused, afraid, and guilt ridden, Diamond Tiara find herself desperate for both redemption and true friends. Luckily, Twilight has three potential friends for her in mind. But can the Cutie Mark Crusaders bring themselves to befriend the pony who has tormented them for so long?
This is meant to play out like an actual episode of the show, theme song and all.
Also, featured here is a special parody song of "I'm a Dentist" from the movie "Little Shop of Horrors". Enjoy!

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

On a dark night filled with even darker magics, an insane cult attempts to give Nightmare Moon a body and life of her own, utterly separate from Princess Luna. But, when the spell is interrupted by Celestia, something unexpected is created.

Now, a little black alicorn filly named Nyx finds herself living under the care of Twilight Sparkle, only to be haunted by memories and emotions from her past. Is she Nightmare Moon reborn or is she simply a doppelganger with a soul and mind of her own? Can Twilight Sparkle protect Nyx from those who refuse to see past her dragon eyes and black coat?

Or, will Nyx be forced to inherit the sins that may not even be hers and become the greatest evil Equestria has ever known?