Part 1: Lyra's Pyro Predicament
Part 2: Twilight's Demoman Devastation
Part 3: King Sombra's Robotic Retaliation

After receiving a strange book from Pinkie known as "The Bombinomicon", Twilight wakes up one morning to find that the mystical tome has been stolen, by...Twilight?

Things quickly unravel as RED Team's Tavish DeGroot (Demoman) and Spy find themselves not only trying to get back home, but also fighting for their lives as villains from the Team Fortress 2 universe combine forces with some of the most dangerous foes Equestria's ever seen!

The sequel to Wayward Courier. Read that first, or you'll get lost.

Two months after his first visit to Equestria, Thomas has returned. And this time, he's not alone!
Now the ponies have to deal with not only him, but a depressed snarky ex-Scribe and a Brotherhood Ghoul with her own list of incredible achievements and emotional baggage.
However, things aren't well in Equestria, as they quickly find out...

All major details relating to Season 3 are non-canon to this fic.

An undead Emperor in need of a new body. A Spartan lost in space. A ragtag team on a suicide mission. What do they all have in common? They all wind up on the magical world of Equestria, where war has been forgotten. That, however, is soon about to change.
When each of them is about to be retrieved, ancient evils arise to unleash hell upon the unsuspecting world. When the forces of three galaxies clash around them, can our favorite ponies hold out against the onslaught?
This is a crossover involving Warhammer 40k, Halo, Mass Effect and MLP, and is also my first fanfic. Comments and reviews are welcome.
Rated T for language, violence, and general adult situations.
Now on Tv Tropes!

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.

Has a TvTropes Page. Please contribute.

Comments contain spoilers. YOU HAVE BEEN WARNED!!!

It was a truly the perfect day in Equestria. That was, until Chuck Norris kicked a hole in the space time continuum and sent countless fictional characters spiraling into the equine world. Will Twilight Sparkle and her friends be able to round up all of them and send them back to their respective realities? Will the ponies even be able to keep their sanity? Probably not.

A Ghost. A weapon. A tool. That's all he's ever known himself to be.

One day he's sent on a mission, a mission to assassinate a high priority target. When he fails that mission, and gets abruptly sent to a certain planet, how will he cope with being taken from the battlefield, and put into a world full of colorful horses that talk?
...
And will he have access to a Tactical Nuke?

Only time will tell in this tale of adventure and comedy!

This story is a sequel to Dark Wanderings

It's been nine months since Twilight Sparkle got back from her solo sojourn to the Capital Wasteland where she met Ethan Smith, AKA that Crazy Son of a Bitch, AKA the Lone Wanderer and was changed forever. Now with Equestria teetering on the edge of a three way war Ethan is called upon to save Equestria, or at the very least to keep Twilight alive. But dark things are awakening in the background and all is not as it seems, can Ethan save Equestria? Can Twilight keep her friends on her side? Will these questions never stop? The answer to at least one of these is yes but can you find out which?

Edited by TacoTown
Coverart by the awesome Derrem

Now has a Tumblr

Tiberium. The infamous green crystal that destroys entire worlds in its wake of global proliferation. It has been a little over a century since the Tiberium threat was first wiped out on Earth, and with it, the primary vestiges of the Brotherhood of Nod. When the GDI advanced humanity to the stars, they found that Earth had not been the only target of the alien Scrin: dozens of other worlds had already been claimed by Tiberium, and the Scrin returned in full force, attacking human colonies across space, stopping human expansion. To fight back, the GDI undergoes a reformation to become the Interstellar Defense Intiative (ISDI) and enacts the Hallman Directive, designed to stop Tiberium spread wherever it may be; such a protocol brings the reincarnated ITC Methuselah to a planet being ravaged by the green crystal, and the forces under Commander Martin Alexandra deploy to stop the threat.

Crossover Material: Command and Conquer - Tiberian Series/MLP
Rated Teen for Graphic Violence and Language

A cold, calculating assassin is teleported to the magical land of Equestria due to the unstable powers of the siren, Lilith. Will our awkward, haiku-obsessed hero be able to adapt to the Magic of Friendship, or will he simply end up murdering everything in sight like he's used to? Let's hope its the former.
Only one thing is truly known, this was a challenge he was NOT prepared for!

Borderlands/MLP crossover. Challenge Accepted.

Cover art by steptrool on DeviantArt