Celestia has a dangerous creature held in the deepest of Canterlot's high-security dungeons. It can create ponies (with full backgrounds and histories) with it's strange and often-times prophetic powers. The Princess does her best to keep it under wraps, but its only a matter of time before it's "creativity" will get out of control.

A human, having suffered due to the mysterious means of his transmission from one world to another, is stuck in bed recovering from his injures. While a little alarmed to find that the one looking after him is not human herself, he can't do much about it.

It helps that - as he finds - she's also rather good company.

For years, Twilight Sparkle and Queen Chrysalis have been at each other's throats. Both have experienced victory over the other, and both have experienced defeat. Out of all the creatures in Equestria, none despise each other the way the pony Princess and changeling Queen do. They seemed destined to remain locked in battle forever, or at least until one is finally dead at the hooves of the other. The cruel insults, the vicious loathing, and the powerful spells that have passed back and forth between them at each meeting have become the stuff of legend.

Imagine Twilight's surprise when she finds out changelings consider this dating.

And now they're married.

***

Sequel: Pony Courtship Rituals

***

Some beautiful fanart of the end of chapter three was done by Dmann892; you can see it here.

More awesome fanart, this time from chapter one.

Now with a TvTropes page (obligatory TvTropes warning goes here).

If you want a Russian translation, you can find it here.

There is now a reading of the story on Youtube, which starts here.

This story is a sequel to Stardust

Times are changing for Equestria as Twilight’s return brings with it news of people and cultures from beyond the peaceful world everypony knows. Aid and volunteers are freely offered to help the besieged humans of Earth because every Equestrian knows that’s what good friends do. Unfortunately, making friends can also have the unintended consequence of making enemies.

When the monsters besieging the humans strike at Equestria with a level of brutality not seen in over a thousand years, the cry for help is sent to all the kingdoms of the world. Honored allies step forth to fulfill ancient treaties and oaths. Enemies, old and new, bury their grievances. An alliance never before seen in Equestria will be created to combat the monsters from the void.

And because of these events, a grim but welcome sibling to the XCOM project is born.

(XCOM/FiM Crossover)
(Sequel to Stardust, which I recommend reading before starting this. Fortitude Amicitia and Broken aren't required reading but are supplemental to the storyline)
(Gore tag for blood and violence)
(Alternate Universe tag because of the divergence from canon that Stardust has caused)
(Uses elements of Season 4)
(Coverart produced by the amazing Carnelian!)
(Many thanks to Arzoo, BradTheBrony, Vandenbz and Setokaiva for prereading!)
(As of 03/07/2016, the prereading team consists of Arzoo, BradTheBrony, Noble Cause and Metallusionsismagic!)
(Complete with it's own TVTropes page as part of the Stardust continuity. Could use some updating!)
(Character tags will be added as chapters are added!)
(Featured 5/12/2014! Thanks folks!)
(Possible spoilers in the comments! BEWARE!)

Isolated from her friends and taken prisoner in the middle of a war, Twilight must deal with the very real dangers of being percieved as an enemy as well as the nightmares of her arrival on 'Earth'. Can she overcome her own fears and the fears of her captors? Will the wayward unicorn's assistance be a boon or a curse to the 'humans?' Most importantly, will she ever find her way home?

"In short, it's a story of friendship and plasma rifles, with the emphasis on the friendship. The characters are well written, the XCOM setting is fleshed out very well, and the story is compelling. If you love XCOM, you'll love the story, but even if you've never heard of it, it's more than worth giving the first 3 chapters a read.

There's excellent action later on, but the real strength lies in the collision between the friendly and naive world of Twilight Sparkle and the desperate world of humans fighting a losing war for survival and willing to do anything to turn the tide."

--Arzoo

(XCOM/FiM crossover)
(Cover art commissioned by a friend and created by the magnificent FoxInShadow!)
(Original cover art by the amazing Carnelian can be viewed here!)
(Gore tag for blood and some violence)
(Many thanks to the studius OminousTen, Arzoo, xXFluttershyForeverXx and finally Setokaiva for giving my rambles a once-over)
(Now with it's own TV Tropes page! Get to tropin' folks!)

Years drifting in space aboard a frigates wreck with nothing to do but wait and think can really wear an AI thin, and when that AI is already past its expected rampancy date, all that thinking time is dangerous. Very dangerous. Fortunately for Cortana, the frigate is pulled into an unknown planets atmosphere, allowing her to take her mind off of rampancy for a while. After being rudely awoken from cryo sleep, the Master Chief, along with Cortana, manages to escape the burning vessel. They have very serious problems though...

They have no idea where they are, or how they'll get back to Earth.

They can only hope someone finds their distress beacon, and fast. The Chief doesn't have many supplies, and with a rapidly decaying AI in his head, he has a lot on his hands. Luckily for them, the planet is life supporting. Unfortunately though, the inhabitants of the strange planet aren't the most welcoming of a seven foot tall alien, especially when that alien is as aggressive and lethal as Spartan-117. The Chief has only one objective, find a way off of the planet. The inhabitants will soon learn, however, that the Spartan is extremely aggressive, and will stray slightly from his objective to harm them if he must. Chief also learns that these beings are no pushovers, and will defend their home and kingdom with their lives.

The first few chapters are mostly to establish a plot, there will be much more action after them. This is also my first fic, so constructive criticism is appreciated. I will be reading the comments quite thoroughly for the first while, so you may see some of your ideas in future chapters. I am only 15 years old, so basically, I have school, homework, and sports that will quite often get in the way of this story, but I will work on it as much as I can when I can. I won't give up or quit in the middle of the story despite what the ratings may be, and last but not least, I won't be turning this into some huge cliche war where Equestria ends up fighting the UNSC and whatnot. Because Equestria would get screwed. Badly. Then the story would be ruined, so, I hope anyone who reads this enjoys!

I do not own the Halo franchise, My Little Pony: Friendship is Magic, or Forward Unto Dawn.

Story added on October 25th. Edited by myself, and inspired by Halo: Ponies and Clouded Pasts by Blazer and The Mercy, Regret, and Truth by Master 4871.

PS: This made it into the featured box the second day it was uploaded, and remained there for a couple weeks. I'm pretty damn proud of that since this was my first fanfic ever, and the first thing I ever posted anywhere. The only other people to read my creative writing creations were my English teachers and occasionally my grandparents and father. So seeing the first thing I submit get such great feedback and a huge amount of views (huge to me), is just amazing to me.

Thanks, bros.

This story is a sequel to Princess Celestia The Changeling Queen: Stories Behind the Mask

At the Royal Wedding, Chrysalis and the Changelings were revealed to all of Equestria.

But another mask was torn away that day. A mask born for a thousand years. A mask created on one promise. A mask, that has become synonymous, fused, to its bearer.

A mask that when ripped off, causes Twilight, her friends and Luna to question everything they ever knew about the one pony, one very important pony.

At the Royal Wedding, the meaning of the phrase 'Princess Celestia' changes forever.

NOTE: Chrysalis is NOT Celestia!!! That'd be impossible to pull off.

Credits to: Plainoasis for the design of the cover art
Note 2: Original cover art here: https://angelea-phoenix.deviantart.com/art/Contest-entry-Changeling-Celestia-337023552

Pre-read/edited by Zervziel,
Blankscape,
FinalFan,
Courage Fire
Aurora Borealis

Side Stories to this can be found: here.

An audio-reading on youtube up to Chapter 21 is up by StraightToThePoint Studios. I'm aware there are others but this is the nearest complete one: [embed]https://youtu.be/X3eMW673CSY[/embed]

There are also 2 print versions of Princess Celestia:The Changeling Queen. Nonexistent Publications run and Ministry of Image's run.

Contribute to the TV Tropes Page (thanks to Babs_Seed72 for getting it up)