Rainbow Dash attends her hometown's Millennial Summer Sun Celebration, where she meets a peculiar pink pony. When a strange portal appears during the testing of Twilight Sparkle's latest invention, and pulls their new companion inside, the two friends give chase and embark on the most important adventure in all of history.

Equestria Daily | TVTropes

This story is a sequel to The Irony of Applejack

Warning: this story is a sequel. Therefore, it is highly recommended that you read the prequel first before continuing!

Over half a year has passed since the changeling attack on Ponyville, and Applejack would like to think things have finally settled down. Much has changed for the young changeling, and all of Equestria in kind. The new district in Ponyville proves that, along with the town's many new residents.
But there is much the young queen does not yet know about being a changeling. Some things, she will learn, can be chosen, while others will be chosen for her. With new allies and enemies emerging all around her, Applejack must discover what it truly means to rule before the choice is taken from her forever, and the history of the changelings repeats itself, once again...

Image provided by Heilos.

Following the destruction of the Collector Base, the crew of the Normandy-SR2 go their separate ways. One squadmate, an AI 'Geth' named Legion, is sent by the Geth Consensus to investigate the possibility of a Quarian attack. However, when Legion is discovered and forced to make an emergency jump through the Mass Relay, it finds itself in the most unlikely of places... Equestria.

At the same time, the ponies of Equestria are dealing with their own problems. A mysterious disease threatens to topple pony civilization, while tensions along the border are growing and could escalate into full blown war.

Join Legion in its journey in Equestria to both return to the Geth before the arrival of the Reapers, and to help the peaceful ponies who inhabit the world.

Notice: As of 9/12/2016, this fic has received comprehensive updates to grammar/spelling/sentence structure, with a few minor plot alterations. Enjoy!

Three weeks after the events of Rainbow Rocks, the sirens are desperate. Without their hearts—the jewels that hold their magic—they have no power. They can't sing, can't manipulate people, and worst of all, can't feed. Their only hope is to restore their hearts, and they need to do it soon, before all three of them starve.

The problem is, they're not sure how to fix the hearts. All they've managed to figure out is that they'll need magic to do it, and magic is exactly what they don't have. Scared, starving, and completely out of options, the sirens turn to the last people who would ever want to help them, and the only ones who actually can: the Rainbooms.

This story is a sequel to Spiders and Magic: Rise of Spider-Mane

Officially Complete!

A collaboration done with Azu.

With the Green Goblin defeated, Peter Parker and Twilight Sparkle are ready to take on their greatest challenge yet: parenthood. They have eleven months to prepare. In the meantime, they’ll also have to earn the trust back of everypony in Equestria, survive Twilight’s hormonal outbursts, deal with Black Cat’s antics, endure Trixie’s sarcasm, and work up the courage to take the next important step in their lives.

Cover image done by Black Freya

In every event, there are a million offshoots and effects, none really able to be fit into a normal narrative. Here is a collection of one-shots and mini-arcs spun out of The Elements of Harmony and the Savior of Worlds, so knowledge of that series will help immensely. Although I will do my best to make it as accessible as possible.

NOTE!:
All side-stories so far take place after the end of The Elements of Harmony and the Savior of Worlds.
The cast will be varied, as will be the stories, but all are canon.

Chapter One: A Picnic by the Lake: Celestia, Luna and Twilight entertain a guest who is more than meets the eye.
Chapter Two: Time Enough for All: The Doctor has spent nearly nine hundred years in Equestria, most it an extended vacation. But news of giants in Ponyville draw him out of semi-retirement.
Chapter Three: Contact Part One: Old Memories: Chip delivers the Princess' message to President Abernathy, which stirs old memories.
Chapter Four: Contact Part Two: Meetings and Greetings: Equestria makes formal contact with Earth, and an old mystery is finally put to rest.
Chapter Five: Family reunion Part One: The Best of intentions: Dinky sets out to reunite her father with his closest friends, roping her sister and the rest of the Cutie Mark Crusaders on a journey across time and space.
Chapter Six: Family Reunion Part Two: Memories: The TARDIS arrives at Earth, reuniting the Doctor with his past.
Chapter Seven: Shape up or Slaughter Out!: Shining Armor gets some help from an old warhorse to finish what he started with the Royal Guard.
Chapter Eight: How Christmas was Saved... Sort of: A short tale of how Santa Claus was saved one Christmas Or Megan had too much eggnog.

Trope page for The Elements of Harmony and the Savior of Worlds. Story listed there as well.

Equestria Daily page: A man can dream...

This story is a sequel to The Elements of Harmony and the Savior of Worlds

The Conversion Bureaus have won. Humanity has been ponified, all traces of our civilization wiped clean from an Earth turned into Equestria. Princess Celestia rules over all, the tyranny of free thought abolished.

Humanity is at the cusp of a golden age. With allies both near and far, biped and quadruped, we strive for greatness, united as never before. Our mark shall be made in space, our influence felt throughout this Spiral Arm.

The Tyrant Princess sees this and is angered. A dome is opened... but this time, humanity is not alone against the Conversion Bureaus.

A spinoff/sequel to The Elements of Harmony and the Savior of Worlds, taking a place about a year after the events there, and my own little 'take' on the Conversion Bureau. This makes it a crossover with Transformers Generation One, GI Joe A Real American Hero and My Little Pony G1.

Thanks to Velkaden for the title. As well as Shubzilla for proofreading, the anti-Conversion Bureau for their help and SJC for help with the look of Megan.

Trope page: Here.
EQD link: ... A man can dream?

Megan Richards is a normal, everyday wife and published author of 'My Little Horsey'... however the tales she writes about aren't fiction, but stories from her past. She thought she put the world of ponies behind her, but sometimes the past has a habit of catching up with you...

G1 meets G4 in a hopefully epic tale of the past, the present and the future.

I own nothing, also, minor cameos from other Hasbro properties such as Jem and the Holograms, Transformers G1 and GI Joe.

Cover image made by the very talented Egophiliac and from here.

fanfiction.net link!
Equestria Daily link... one of these days.
TV Tropes page
All the Tropes page

Sequel: The Conversion Bureau: United We Stand

Side-stories and mini-arcs not able to fit into the main narrative: Side Stories of First Contact

The story is generally the same. A group of ponies go on a quest to stop an insane alicorn who had escaped banishment, learning about friendship along the way and mastering the Elements of Harmony. But the details...

It can be Trixie Lulamoon leading the Elements of Harmony against Corona.
Rainbow Dash could be Celestia's student and go to Ponyville.
Equestria could have a deep connection to three young people in its distant past.
The Elements of Harmony could have been moved to Manehattan for the ponies to quest for.
Princess Cadance might rule over an Equestria of music, with Octavia as her prized protege.
Or Spike and Twilight might have their roles reversed, the former a stallion and the Element of Magic.

And each one has been chosen by Discord, an Element removed to a seventh Equestria for purposes as yet unknown. Can they survive? Can they get home? Read and find out!

The Lunaverse was created by RainbowDoubleDash and is used with permission. Opening segment was written by Talon and Thorn.
The Hasbroverse was created by RK_Striker_JK_5 and is used with permission.
The Manehattanverse was created by Little Jackie Papercut and used with permission.
The Cadanceverse was created by GrassAndClouds2 and used with permission.
The Flipverse was created by Bed Head and used with permission.
The Dashverse was created by Trinary and used with permission.

And special thanks to dramatic_spoon for getting this all together.

This story is a sequel to Avocation

Life in Ponyville has been relatively quiet recently, which is somewhat surprising, given that the town's librarian tried to usurp the Equestrian throne only a few months ago. Aside from the appearance of a grumpy pegasus who set up shop as a cloudsmith, the aftermath is so unnoticeable that most ponies aren't even aware that the incident happened at all. Unfortunately, all that's about to change, thanks to the return of a certain revenge-obsessed showmare....

This is the fourth story in The Petriculture Cycle; reading the first three stories, which begin here, is highly recommended.

The artwork was provided by Page Turner, and the TV Tropes entry can be found here.