This story is a sequel to Iron Hearts: Book 1 - Planetfall

An MLP/Warhammer 40K Crossover, part 2.

Celestia has handed down her order. The Iron Warriors must be defeated and driven from the planet, lest the corrosive grip of Chaos infect their world. With great reluctance, Twilight and Company depart for the Iron Warriors fortress-factory in order to confront the Chaos Warsmith. However, in this mission it is not the might of the enemy that will be their greatest challenge, but their own burgeoning friendships with the admittedly less-than-saintly members of the 38th Company.
At least until the Iron Warriors actually consider them a threat. Then it's totally their military might that will prove to be their greatest challenge.
All the while, the Tau forces lick their wounds and plot their next move. They are far from defeated, and the Iron Warriors have little inkling as to the aliens' true purpose.

MORE EXPLOSIONS!!

(Dark humor warning; minor grimdark)
(Cover art by Nicholas Kay)
(This series now has its own TVtropes page!)
(This series is a contestant in the Tournament of Canterlot, a charity event to raise money for Syrian refugees! Go here for details and donations!)

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 Iron Hearts: Book 4 - Emerald Dawn

An MLP/Warhammer 40K crossover, part 5.

With their plan established and put into motion, the 38th Company begins the long and unwieldy task of planetary defense, fueling the arcane energies that may yet unsteady the Empyrean and spare their fleet from an enemy without number or mercy. The inhabitants of Centaur III and even the abandoned aggressors help where they are able, but as their foes grow in number and destruction spreads across the planet, the war for the Centaur system has become a bloody race against time.
All the while, the grim culture of the Chaos marauders continues to mingle with the enlightened benevolence of their equine allies. Tempers fray and allegiances blur. But the die has been cast: Equestria and the Company will survive together, or be snuffed out together.
And even should they succeed, what future awaits these unlikeliest of friends?
For there is no peace among the stars. Only an eternity of carnage and slaughter, and the laughter of thirsting gods.

ALL THE EXPLOSIONS. JUST, ALL OF THEM.

(Cover art by Ahrimatt)
(This series now has its own TVtropes page!)
(This series is a contestant in the Tournament of Canterlot, a charity event to raise money for Syrian refugees! Go here for details and donations!)

This story is a sequel to Iron Hearts: Book 3 - The Sept Lamman

An MLP/Warhammer 40K crossover, part 4.

The Tau threat has passed. The fleet that once thought to sweep aside the tainted pirates of the 38th Company has fled the system. The Lamman Sept is broken, demoralized, leaderless...
... And victorious.

With Lamman's plan put into motion, an alien horde hurtles through the Warp toward the Centaur system, its soldiers without number and thirsting for violence. Equestria's heroes must find a way to stop them, or the entire planet will be overrun with ease and its inhabitants butchered. While they could afford some pretense of neutrality and disinterest in the fight between the Iron Warriors and the Tau, now it is their world that lay in the crosshairs of the foe. Ponykind will need help to survive, and they look to the forces of Chaos for aid. But is there any hope to be found in the darkness?

EXPLOSIONS ARE IMMINENT.

(Dark humor warning; mild grimdark)
(Cover Art by Ahrimatt)
(This series now has its own TVtropes page!)
(This series is a contestant in the Tournament of Canterlot, a charity event to raise money for Syrian refugees! Go here for details and donations!)

This story is a sequel to Iron Hearts: Book 2 - Ferrous Dominus

An MLP/Warhammer 40K crossover, part 3.

The formal negotiations between Equestria and the Iron Warriors have failed. Yet peace and even cooperation between the harmonious ponies and the corrupted militants blooms in the dark corners of Canterlot and the open streets of Ferrous Dominus. The Elements of Harmony are safe, trade flourishes, and cautious meetings grow into lasting friendships as an unsteady calm descends upon both forces.
Even the Tau threat seems to have mysteriously vanished as the Iron Warriors refuse to assault their hideouts and risk springing the traps of the Fire Caste.
But the Tau have not vanished. The Lamman Sept of the Tau Empire, the Fire Caste's hidden dagger, have come to grips with the slumbering giant looming over their doorstep and have moved forward into the final phases of their plan. Fleets ply the void, hunters stalk the orchards, and in the depths of the badlands a strange device is rapidly assembled for purposes unknown.
The Tau alone know that time is running out, and more than just the fate of Centaur III hangs in the balance.

SIGNIFICANT POSSIBILITY OF EXPLOSIONS.

(Dark humor warning; minor grimdark)
(Cover art by Ahrimatt)
(This series now has its own TVtropes page!)
(This series is a contestant in the Tournament of Canterlot, a charity event to raise money for Syrian refugees! Go here for details and donations!)

When Twilight Sparkle slipped beneath the covers last night, everything had been fine. She had friends whom she loved, a teacher she adored, and a bright future ahead of her. But when she woke up, her blankets and quilts had been replaced by hospital gowns and padded restraints.

Everything is wrong and nothing makes sense; even her friends have changed. The doctors keep telling her that she is sick, that none of it was real and that it was all in her head. Yet she remembers a life far beyond the hospital walls. She couldn't have made it all up on her own. They must be lying… right?

Ask Asylum Twilight - Still updating regularly!
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The Asylum 20,000 View Spectacular Stage Show!

Art:
Asylum Cover by conicer
Twilight and Twilight Smiles by dreamingnoctis
Mirror Twilight and Plague Doctor by Jaestring / BloodGoldWings
Twilight Smiles and Doctor AJ by conicer
Nurse Ratchet and Silas and What's in the mirror? by Archonix
Doctor AJ Sketch by Archonix | Colored and vectored version by ReFro82
Twilight's Asylum by Khan the Cake Lover
Smilight by HappySwitch
Twilight Waking Up by Dombrus
Fan Art by toxicdemon10
Asylum Twilight by Madness-With-Reason
Asylum Fluttershy and Asylum Ch 26 by Downburst-Backspace
Twilight and her Twin by v747
Birdgirl by sirValter

Readings and Videos:
Asylum Animated Trailer Video by formuladash
Reading by Gammarobot (SugarCubeRadio): All Chapters Here
Reading by Ender Brony: All Chapters Here
Reading by VisualPony: All Chapters Here
Reading by MelancholyIguana: All Chapters Here
Fan Trailer by Kaidan: Asylum FanFic Trailer Cuckoo's Nest

Sanctuary by Kaidan
Broadhoof Files: Dr. Humors by TypewriterError
Broadhoof Files: Corporal Phalanx Spear (Ret.) by Phalanx Spear
A Hearth's Warming Tragedy by Seven Fates

A special thanks to Breath of Plagues, Rex Ivan,
ChudoJogurt, Cynewulf, Death the Kid, Selbi, PrinceDolph, Blahman2816, Queue, and Gage!

Axan Zenith - Dr. Dreamer
Dratini4 - Way Finder
psychicscubadiver - Bright Mind
Velkaden - Dream Chaser
Reese - Silver Glow
Viola Heartstrings - Clover
Archonix - Spinney Whiteacre

This story is a sequel to Twilight Hears The Narrator

After her odd encounter with the mysterious entity, Twilight has grown rather accustomed to living with the voice of a narrator following her life. Although she still doesn't understand his presence, she has begun to accept him as a friend. But the confusion only grows, as the Narrator finds himself following the stories of other ponies. And Twilight will soon learn that she is not the only one who can hear the voice of the handsome, talented, witty, charming, manly gentlecolt yours truly!

Twilight's latest creation was meant to allow them a glimpse of civilizations not of their world. What they hear however, is more saddening, beautiful, and inspiring than they could have imagined.

Ponies picking up human transmission story for fun. Hope you enjoy.