Please READ the description first:
This story is indeed AU, though not by a whole lot, less as AU as my previous Stargate crossover. Hope you enjoy the past 6 weeks of toiling...

Artwork by: mercscilla on DA

In 2011 a small fleet of ships dispatched from Atlantis arrive in an strange mystical reality when a mission on the hunt for Genii leader Augustus Kolya goes horribly wrong. The Atlantis expedition force now stranded in this new reality must find a way back, but also take the time to explore this strange world of Magic and Ponies. Join Sheppard, Carter and others in their adventures.

2022 REWRITE IN PROGRESS

After being rudely awoken from Cryo-sleep, John-117 finds that the Forward Unto Dawn has been sucked into a gravity well, causing it to fall towards an unknown planet. In the crash, he is separated from Cortana and falls alone into the Everfree forest. In addition to this new complication, old memories from a scarred and tragic past haunt his dreams, putting his remaining sanity on edge.

However, he has little time to ponder these thoughts, as he encounters the planet's... peculiar... inhabitants.

First 19 Chapters proofread by Bravo 539 and Shadownamesto.
Credit for the intro sequence goes to Blaze Spectrum.

Current rewrite will not necessarily follow the old story but certain events and details may be reused.

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!

XCOM Record: Operation: Rising Star
11:52 am, 18th Febuary, 2016
Northwestern Territories, Canada.

Summary: Witness reports contact with extra-terrestrial creature. X-ray is unconcious and unresponsive. X-ray does not match description of previously observed species.

Response: Strike-One dispatched on high alert, orders are to recover X-ray alive. Alien Containment prepared for the new arrival.

***

The war ended. They were beaten back, their mothership destroyed, their command structure in ruins. Lost ships and soldiers continued in vain, but thanks to XCOM, humanity won, and the world was saved. The Volunteer saw to that - everything changed because of one man.

And then suddenly, everything changed again. Only this time, it's not a man's doing - it's a mare's.

Proofreading by the aweome Setokaiva, entirely without me asking!
Tagged Dark and rated Teen: Gore, because there is going to be some blood shed by the end of this.

A story written as a series of 100 word drabbles. When Tirek took Twilight's magic, he also took something else this is that event, and the aftermath. AU ending to the season 4 finale. Rated T for carefully worded character death.

Just in case anyone is confused (and because I could only add 5 character tags) Other characters involved are Shining Armor, Twilight's Parents, and Spike.

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

Twilight isn't having a very good day. An experimental spell blew up in her face, an army of changelings is attacking Canterlot, and she just died. Yet somehow, it looks like it's going to keep going downhill from here.

Given the chance to correct what's gone wrong, Twilight swears she's going to fix all this even if it kills her. Which it will. Frequently.

Cover art by Pixel Prism
Spanish Translation
Series TV Tropes page

I'm dying.
Soon I will leave everything and everypony behind. No more picnics with my friends or tea with Celestia.
For now all I can do is say goodbye.

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!

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One year after her coronation, Princess Twilight Sparkle is dead, killed by her own subjects out of fear and jealously. After the funeral, Princess Celestia isolated herself from the world, mourning the loss of her brightest student and daughter figure.

But she cannot weep forever. She must take control of her duties once more. Haunted by the memories of the assassination, and its aftermath, Celestia slowly makes her way to Twilight's resting place to find some closure.

Now With its own TV Tropes Page!

Sequel is up