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!)

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 )

After being freed from their bonds, the Emotional Entities seek out a world where they can live in peace and harmony. What better place to live than Equestria, a land which embodies the very powers of will, hope, compassion, and love. But can the entities of the Emotional Spectrum fit in with the pony race? And can they truly escape the turmoil of the universe they left behind, or will a new War of Light be ignited?

Edit: New cover art, courtesy of myself.

Discord's statue has vanished from where Celestia had put it in the royal dungeons, but it doesn't seem to be because Discord himself has escaped. Rather, somepony has stolen it. Now the Doctor and his loyal companion Derpy will search time and space to find the culprit. Bring on the drums!

Now with a TVtropes Page.

Written in collaboration with CommacazyFreak.

The new cover image is provided by sophiecabra, found here. Used with permission.

Diablo Crossover.

The Archangel of Justice destroyed the Worldstone to spare Humanity the corruption Baal infected it with. The force of its death knell shatters Mount Arreat and sends Tyrael hurtling across the endless planes of reality. He falls upon a world untouched by Angel or Demon, far from the sight of the High Heavens. So far, in fact, that he fears he will not be reborn from the Crystal Arch.

Wounded and near death, hope appears in the form of two strange creatures bearing the power of night and day.

Tyrael now faces a time of recovery as his power slowly heals within a body fashioned for him by his saviours. Justice Incarnate tastes for the first time the life of a mortal, and it is a strange, confusing experience .He has been left in the care of one Twilight Sparkle to learn of this world.

After all, where better to find peace and harmony than Ponyville?

Act I - The Root of Evil
Act II - ????????
Act III - ???????
Act IV - ???????

[Cover image used with full permission of the owner. Go on, go have a look at Chagial's stuff.]

Due to a combination of blood magic, an ancient elven artifact and the well placed punch of a golem, the Commander of the Grey and several of his fellow Grey Wardens find themselves in the magical land of Equestria.

Coming from a land that not only has magic, but fears and mistrusts those who use it, how will they react to see land of ponies who depend on magic to keep their lives in perpetual harmony? How will the ponies react to the strange creatures coming from a land of bloody conflict, demons and magical intolerance?

A Dragon Age crossover.

Everything changes for Twilight Sparkle and her friends when a mysterious extraterrestrial ship crash lands in Equestria. When Twilight messes around in the ship's systems with her magic, she ends up transported to an alien world unlike anything she imagined: a box canyon in the middle of nowhere.

To get home, Twilight must enlist the help of the eccentric Red and Blue soldiers that live there... if she can get them to stop bickering first! Additionally, she finds herself being pursued by the enigmatic military agency known only as Project Freelancer. Back in Equestria, all is not well for Twilight's friends as forces involved with the crashed ship make themselves known. Reds, Blues and ponies will all have to work together to discover the mysterious connection between Equestria and Project Freelancer.

A crossover with Red vs Blue. Written with the intention for the story to be followable without having watched the series. (just don't expect to get all the references).

Now with editors! BradtheBrony and Rough_Draft.

I made a blog post explaining things. You should read it.

TvTropes Page.