Princess Celestia: Goddess of the Sun, ruler of Equestria, beloved Princess of ponies. She is loved by all, and loves all in return. A calm and wise ruler, she sits on the throne in Canterlot, maintaining peace and harmony throughout the land.

What most don't know is that her past is much darker: She was once a commander of legions, a warrior and scientist of unmatched skill. Thousands of monsters and abominations fell to her forces, slain in the name of an old leader, one entombed within his own throne. Free of her old form, free of the powers of Chaos, she was cast into a new realm, in a new form, with a new lease on life.

She is the God Emperor, Eternal Ruler of Equestria and Lord of the Imperium of Man.

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Comments contain spoilers. YOU HAVE BEEN WARNED!!!

This story is a sequel to The God Empress of Ponykind

A message rings through the Warp: "The Game is broken, only Destruction remains". Celestia hears it, fearing for the lives of her former subjects and those of her beloved ponies. Unwilling to sit idle, she has chosen a dangerous path: return to the Imperium, take up the mantle of Emperor of Mankind, defeat the coming storm, and save Mankind once and for all.

With Twilight Sparkle to aid her, Celestia faces new challenges and new enemies. Her forces are scattered, her people assaulted, and the enemies of Man grow stronger with each passing day.

The Time of Heroes is gone. Now comes the Time of Ending.

Sequel to God Empress of Ponykind. Reading that first is strongly recommended.
Rated T for 40K related violence, but that might change at some point.
Comments contain spoilers. You have been warned.

Captain Flowers thought it would be just another ordinary day. Be there for his men, keep the fighting to a minimum, and make sure nothing bad whatsoever happened to Church. Just like any other day in Bloodgulch.
And then the little pony appeared and refused to let go of his charge. This was going to be interesting...

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Part of the PWNY-verse.

Another side of the story is being written by cyberlord4444, and can be found here: https://www.fimfiction.net/story/386172/rock-in-the-gulch-analysis-anarchy

Edit: New Cover Art by ProfessorCatPro
Edit 2: Fan art by Cookie_Girl! So adorable!

Conceived in the minds of multiple children and adult children across the nations since the 1980s, the three big Hasbro properties stumble into one another in a surprising way. Written with the intention of being introductory for most readers, with prior knowledge not being required.

Soon after the Autobots and GI Joe become aware of one another and team up against the forces of COBRA and the Decepticons, a joint mission to spy and sabotage an enemy base finds the stakes growing higher and the surprising getting much cuddlier and littler when something very unexpected comes through a portal. What happens when two (semi) series franchises find someone from a gag series wandering about? Find out as heroes team-up, villains are left perplexed as two thirds of their enemies are, and someone let the pony drive!

"YO, ROLL OUT JOE!"

GI JOE, Transformers, and My Little Pony owned by Hasbro

The Princesses find an alien creature barely clinging to life at the scene of a terrifying crash. Can the Combined Power of the Elements of Harmony save it, or more importantly, should they save it? Will the arrival of this strange creature tear Equestria apart?

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https://tvtropes.org/pmwiki/pmwiki.php/FanFic/Article2

This story is a sequel to Sunset Shimmer is MAD about EVERYTHING

The mysterious Table of Harmony has called on Starlight Glimmer to solve a friendship problem at Canterlot Castle, but wait! A second cutie mark belonging to a magically inclined alicorn has appeared, and unfortunately for Twilight, it’s not hers.

Can Sunset Shimmer help Starlight Glimmer untangle this mysterious problem in Canterlot, or will her own personal past prove more a hindrance than anything?

Spoilers for 'A Royal Problem'

Sunset vector by Sunsetmajka626.
Starlight vector by Cloudyskie.

Sunset Shimmer, twice savior of Canterlot High who earned her wings by using the combined magic of the Earth elements of harmony to save the world from Twilight Sparkle (you know... the one with the glasses). She's offered to help Twilight's (you know.. the alicorn Princess of Friendship) new student learn about friendship while the whole crew embarks on a trip to the Crystal Empire. This should be a fairly relaxing and stress free trip. Right? RIGHT?!

It should go without saying, but MAJOR spoilers to the season 6 premier.

Sunset vector by mighty355. Other cover art stuff by Novel Idea!

Principal Celestia has accidentally fallen through the mirror into Equestria, and it may be a bit before she can go home. Until then, she has to learn to cope with a strange world, in a strange body.

At the same time, Twilight has to figure out how she can help her new guest while keeping Equestria from freaking out over the presence of a second Celestia, and Sunset Shimmer has to figure out how she is going to make amends with those she had left behind in Equestria, while keeping an eye on her Principal.

Disclaimer: Since I wrote this description ages ago before I even knew the plot, the story is mostly pure comedy in the beginning, with eventual Sunlight and Chryslestia shipping!

Cover image by Arvaus, used with permission.

This story is a sequel to Destinies

Nearly a year has passed since the events that had brought two realms together. Each had kept the other a secret until now, two worlds separated by a certain cartoon. Finally, both are ready to deal with the inevitable complications, to realize the benefits of trade: human technology for Equestria, and magic for humanity.

The Princess of Friendship is convinced she‘s up to the task, while Meg‘s doubts over the true meaning of her cutie mark grow as the two worlds converge.

Read Destinies first. You won‘t have any idea what‘s happening if you don‘t.

Pre-reading and editing by Mitch H, Doggyshakespeare, and darkszero.

As vital to the Guardian as a Ghost becomes, the meld of metal and Light is little more than a trinket when alone. When such separation occurs, most slowly degrade into a crusty husk, devoid of life and Light.

When his Guardian is consumed by the Darkness, one such Ghost breaks the mold of decay to fulfill the legacy of his mentor and friend, scouring the far reaches of the galaxy with the incomprehensibly intricate technology of the Vex.

The Ghost stumbles upon a world he could not have imagined, a place untouched by both the Darkness and the Traveler's Light. Discovering a secret Vex plot which threatens to devour the innocent planet, the Little Light does the unthinkable yet again. He takes upon a second Guardian, one bestowed with the rare gift of his previous. Kindness.

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