After Starlight Glimmer's misadventure beyond the Magic Mirror, Twilight Sparkle creates an artifact that will allow its wearer to travel between planes of existence without allowing excess magic to leak from one world to another and upsetting the delicate balance of worlds.

In doing so, however, she soon discovers more about herself and the spark that awakened the Element of Magic than she could have ever anticipated, and learns of a secret that Celestia had been keeping from her all her life.

Stranded in the world-spanning city of Ravnica, Twilight Sparkle must now seek to understand herself and the strange new plane of existence she's found herself in, and come to terms with her own role in Equestria and the Multiverse.

A Magic: the Gathering crossover. Cover art by Beavernator on DeviantArt.

Celestia and Sunset's fights were getting out of control so with that in mind both decided to take a break from their mentor/student relationship.

With a lot of time at Sunset's disposition Celestia offers the unicorn a change of pace and perspective and shows her the portal mirror, but this time instead of the Equestria Girls world being at the other side instead Sunset finds a world where magic hids behind secrets and spells.

Accepting the chance to study at the prestigious Hogwarts School of Witchcraft and Wizardry, Sunset will find herself in the middle of a war between good and evil; will a unicorn that hasn't been touched by harmony be capable of fighting the addictive power of dark magic or will she become a pillar for Harry and his friends?

What is known is that Hogwarts and the english wizard world are not prepared for the craziness and shenanigans of Sunset Shimmer.

Originally part of The Many Destinies of Sunset Shimmer.

Celestia, sacred paladin of the Solar Knights, has been on many journeys to the perilous Everfree Forest in the name of defending her kingdom from all kinds of magical menaces. But when she takes on a mysterious witch in the heart of the forest, she finds the values at her very heart challenged by the treacherous venture. Her quest to defend faceless subjects from a dangerous entity becomes one to save a troubled soul from its own misery, and, in the process, perhaps heal the pain buried deep within her own.

An MLP/Warhammer 40K Crossover

The Iron Warriors 38th Company has landed in Equestria, entrenching themselves like a barbed hook. They hunt the aliens of the Tau Empire, intent on destruction and pillage.
A small squad is dispatched on a reconnaissance mission, only to find that there is intelligent life on this world besides the feuding space-farers.
Will these improbably adorable and friendly equine aliens turn the damned warriors of Chaos from their blood-soaked path, cleansing them of their dark legacy with the magic of friendship and harmony?

No.
No, that isn't happening.
EXPLOSIONS!!

(Dark humor warning; limited grimdark themes)
(Cover art by Nicholas Kay)
(This series now has its own TVtropes page!)
(This story is a contestant in the Tournament of Canterlot, a charity event to raise money for Syrian refugees! Go here for details and donations!)
(Featured on Equestria Daily 8/20/15 )

This story is a sequel to The Dark Ones

Many years after the destruction of Equestria, Twilight Sparkle serves the Imperial Inquisition in its war against those responsible. Having thought her past safely buried, what will become of her when it returns with a vengeance?

Remember: if you fave, like!

Have some fanart, with thanks to NCMares!

Featured on TV Tropes!

A situation with the Dursley family gets Harry sent off to America to live with his mother's cousins, Principal Celestia and Vice-Principal Luna. Of course this brings a whole new set of problems to both the world of wizards and the girls of Canterlot High School.

King Sombra’s dark influence was obliterated by the Crystal Heart, and the villain is well and truly dead. But when he attempts to steal the afterlife of an innocent victim, a human spirit is left hurtling towards Equestria, where this unfortunate soul is revived into the only vessel available: the reconstituted body of King Sombra himself.

Thus, a cheerfully oblivious alien is crammed into the form of the most evil and malicious being Equestria has ever known. Not that Shining Armor and Cadence know this, of course. As far as they are concerned, the King is back and he’s lost his fricking mind.

Click here for the TV Tropes page!

During the battle with the changelings, a trapped Discord manages an undirected spell that reaches across universes to bring an agent of chaos to Equestria. What's brought back more than qualifies.

Steam! Gears! SCIENCE! A very confused Spark! And, eventually, really good coffee.

Here comes Agatha Heterodyne--MARE GENIUS!

This story is a sequel to Metroid Equis

With the culmination of events on the BSL Research Station, Samus Aran is finally able to come back to Equestria, Planet Equis; to come back home. Much has changed in her absence, but it is still the friendly, peaceful, welcoming planet and nation that she left behind two and a half years prior. With the Space Pirate threat neutralized and the secret, illegal Metroid militarization programs destroyed, it appears that Samus can finally take another massive breather with her friends and enjoy some well-deserved rest, recovery, and relaxation. The galaxy is finally at peace.

At least... for a short while.

A new enemy, one much closer to home, soon rears its head, threatening all of Equestria and Equis with complete and utter annihilation. Their mission: revenge. Samus will fight with all of her being alongside her allies against an enemy who would like nothing more than to see all that she holds dear, including her home planet, completely razed. In so doing, her cunning, ever determined enemies unleash a weapon so unexpected, so eerily familiar yet horrifically foreign that even Samus herself just might prefer the late Ridley or the SA-X...

Editing Team: Random_Dragon; ToxiClay

The Metroid Timeline/Chronology (confirmed by Nintendo) can be found here.

Canon Considerations
MLP-FiM: Up to AND including "Magical Mystery Cure." (Seasons 1, 2, and 3)
Metroid Series: Everything up to AND including Metroid Fusion (Including original mangas. See official timeline above). So, effectively everything.

After the battle against Ragyo Kiryuin, Senketsu did not truly perish.

Traveling across the universe as a Primordial Life Fiber, he falls to a new planet in pursuit of a dangerous enemy and must now fight to protect this world from destruction. His only hope rests in mysterious boy who takes him to a school full of talented youths in search of one who can wear Senketsu and unleash his power. They will fight with everything they have to prevent the scourge of Life Fibers from claiming another planet.

A Kill la Kill crossover.