X-Com and Mass Effect Crossovers
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Sparatus' Folly by Carthienes reviews
A series of snippets telling the story of the Human-Citadel war, fought between the Human X-Com and the Turian Hierarchy. Originally published on Reddit. Based on the original X-Com UFO Defence (1994), not the Reboot!
Rated: T - English - Sci-Fi - Chapters: 14 - Words: 21,693 - Reviews: 65 - Favs: 260 - Follows: 313 - Updated: 2/26/2022 - Published: 2/14/2022 - Complete
XCOM: Operation Pathfinder by K Fire0210 reviews
Dr Tygan has, on the orders of the Commander, been studying an orb of some kind that appeared out of nowhere in the North American region. This orb happens to be a gateway to another dimension and some of its inhabitants have been dumped into the year 2035 on a world run by aliens. These adventurers are not prepared for XCOM's method of war or its attitude to non-humans.
Rated: T - English - Sci-Fi/Adventure - Chapters: 3 - Words: 4,151 - Reviews: 8 - Favs: 40 - Follows: 76 - Updated: 12/6/2019 - Published: 11/23/2019
X-COM Ad Infinitum by Xphonias reviews
X-Com, Mass Effect Crossover, Space Engineers elements. As Humanity pushes off the Ethereal threat a cycle continues, while a vast, unknown Galactic Civilization lives right upon its borders, bringing with it possible friends, or foes.
Rated: T - English - Sci-Fi/Adventure - Chapters: 7 - Words: 6,725 - Reviews: 15 - Favs: 104 - Follows: 156 - Updated: 10/25/2019 - Published: 3/25/2018
Unknown Crime by ecarden reviews
One shot in my Unknown Contact Universe-adapting legal systems to a post-Ethereal Invasion world. Warning: Contains legalese (lots of) and references to sexual assault (sort of).
Rated: T - English - Sci-Fi/Crime - Chapters: 1 - Words: 2,690 - Reviews: 3 - Favs: 9 - Follows: 7 - Published: 7/29/2018 - Complete
The Human War by Generatedname reviews
The Citadel Council is a peaceful conglomerate of races, blissfully unaware of the horrors that lurk beyond their space. Humanity, meanwhile, is a race that has fought against these alien horrors ever since they made contact. What will happen when the two societies meet? Will peace follow war? Or is the Citadel Council doomed to fall to humanity? Rewrite of When Civilizations Meet.
Rated: T - English - Sci-Fi - Chapters: 13 - Words: 138,222 - Reviews: 737 - Favs: 2,045 - Follows: 2,660 - Updated: 5/30/2018 - Published: 3/29/2016
The Human War: Tales from the Front by Generatedname reviews
A collection spot for side stories taking place in the world of The Human War that I thought would be nice to write up, but don't quite fit into the primary narrative.
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 6,044 - Reviews: 3 - Favs: 78 - Follows: 93 - Published: 1/9/2018
Psi Effect by Cap'n Chryssalid reviews
A fun-loving asari mercenary finds herself a little in over her head when she ends up abducted by terrifying aliens from beyond the galactic frontier. These asari-like creatures call themselves 'humans.' They seem to be secretly nosing about on the borders of known space, acting through proxies, conducting covert operations, and they've got a deal for an enterprising asari...
Rated: T - English - Humor/Sci-Fi - Chapters: 43 - Words: 387,570 - Reviews: 1460 - Favs: 3,860 - Follows: 4,399 - Updated: 1/2/2018 - Published: 7/19/2014 - U. Wrex, Daro'Xen, J. Garson, OC
Xcom: Incursion by Drewman784 reviews
Every race thus far has utterly failed to stop the Reapers, always embroiled in pesky politics and wars to take any notice of the coming storm. This time though...this time is different. Can you feel the equally raging storm coming? I can. Can you? Side story: Incursion: Alliance Effect *Earlier chapters rewritten. Discontinued*
Rated: T - English - Suspense/Adventure - Chapters: 11 - Words: 39,880 - Reviews: 128 - Favs: 281 - Follows: 361 - Updated: 8/3/2017 - Published: 11/28/2015
Reparations by Gregg Landsman reviews
One hundred and seventy years after the Temple Ship, humanity has spread out among the stars and found to their surprise that the aliens they thought of as monsters and conquerors were saints and jerks just like everyone else. That and as it turns out the Ethereals were really, really sorry.
Rated: T - English - Adventure/Humor - Chapters: 4 - Words: 32,323 - Reviews: 84 - Favs: 368 - Follows: 473 - Updated: 6/17/2017 - Published: 1/24/2017
XCOM: The Resurgance by Halofan5695 reviews
When a sarcastic, rich, genius, loses his parents to slavers. He goes out in the galaxy for revenge on that Batarian. All the while, rebuilding an old organization, and discovering something worse than Batarian slavers.
Rated: T - English - Sci-Fi/Drama - Chapters: 1 - Words: 4,357 - Reviews: 3 - Favs: 20 - Follows: 22 - Published: 3/14/2017 - OC, Liara T'Soni
XCOM: Impact by timedraven117 reviews
The Inusannon, and the Protheans, failed. The Cycle continues. One Inusannon breaks. Another teaches. And the youngest, fights. Humanity will take a central role in leading the charge of the future. The Reaper's days are numbered. Indeed, it is the beginning of the end. A war that will shake the galaxy and will never be seen again.
Rated: T - English - Sci-Fi/Supernatural - Chapters: 6 - Words: 32,013 - Reviews: 33 - Favs: 122 - Follows: 173 - Updated: 1/2/2017 - Published: 11/10/2015
The New One's Destiny by SniperInTheHouse reviews
You only get one chance at life right? Marcus learns the hard way that's not the case. Thrown into a different universe with just his wits and hatred for xenos will he tear Shepard's crew apart or be the wild card they need to defeat the collectors, and what's with these dreams haunting Marcus and humans getting along with aliens.
Rated: T - English - Adventure/Mystery - Chapters: 17 - Words: 63,083 - Reviews: 54 - Favs: 59 - Follows: 77 - Updated: 12/28/2016 - Published: 11/7/2012 - J. Garson
Of Psychics and Flying Chthulu-ships by Dr1ft3r0I reviews
The Volunteer ended the war. Now he and the best of X-Com are stuck in a world that they don't know, surrounded by aliens that may or may not want to kill them all. Oh, and there's a giant metal cuttlefish in the sky. Starts post X-COM: EU, beginning of ME1. Not CRACK!
Rated: T - English - Adventure/Sci-Fi - Chapters: 6 - Words: 26,036 - Reviews: 50 - Favs: 186 - Follows: 326 - Updated: 12/25/2016 - Published: 4/29/2015 - [J. Garson, Garrus V.]
Incursion: Alliance Effect by Drewman784 reviews
We all remember the First Contact War, the brief but devastating contact war between the Species Alliance and the Turian Hierarchy. But now the war is over and diplomatic relations are being established as we speak. So the question is, what happens now after the war is over? *Side-story to Xcom: Incursion*
Rated: T - English - Sci-Fi/Suspense - Chapters: 3 - Words: 8,161 - Reviews: 3 - Favs: 57 - Follows: 67 - Updated: 12/20/2016 - Published: 10/2/2016 - Complete
X-Com: Contact Wars by Zanji of clan okami reviews
First contact it was supposed to be great moment in history, but it lead to only war. What followed was the beginning of a clash between civilizations that would shake the very foundations of the galaxy. (A little crossover that's type has never been done before) T for now
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 643 - Reviews: 1 - Favs: 8 - Follows: 11 - Published: 9/30/2016
Vigil by Peptuck reviews
Mankind has survived its crucible, and while scarred and changed by the Ethereals, they advance into the cosmos. The galaxy beyond is a place of wonder and terror, of wealth and strife. Amid the threats and opportunities, both within and without, XCOM remains vigilant. Mass Effect/XCOM/Eclipse Phase/FEAR/Destiny fusion.
Rated: T - English - Sci-Fi/Adventure - Chapters: 18 - Words: 170,804 - Reviews: 426 - Favs: 1,066 - Follows: 1,148 - Updated: 9/14/2016 - Published: 9/2/2014
Ethereal Effect by Barrour reviews
It seems that all hope is lost for the mankind, XCOM has been wiped out, human rebellion is being crushed and majority of Ethereals are already transferring their consciousnesses into the new Avatar bodies. Only Commander knows that with defeat, humanity has bought itself a chance to endure the storm that is sure to come. And for the sake of humanity, no sacrifice is too great.
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 2,612 - Reviews: 11 - Favs: 47 - Follows: 54 - Published: 8/7/2016
The XCOM Reports by Sage of FanFiction reviews
XCOM, I started the story but had a hard time fitting everything together, so I decided to post these and let you readers fill things in with your own imagination.
Rated: K - English - Chapters: 16 - Words: 13,545 - Reviews: 3 - Favs: 12 - Follows: 8 - Updated: 7/25/2016 - Published: 6/5/2016 - Complete
I Watch, I Believe by Nenshou Yuuki Medic of Aincrad reviews
Humanity has survived the Ethereal war and begun to spread it's wings across the stars, constantly vigilant against the threat that the Ethereal's warned them of, but there is already an established order to the galaxy, will they co-exist or will they have to raise their weapons once more. Whatever the case is, X-COM is ready. Vigilo Confido.
Rated: T - English - Adventure - Chapters: 1 - Words: 1,371 - Reviews: 9 - Favs: 36 - Follows: 60 - Published: 6/10/2016
When Civilizations Meet by Generatedname reviews
The Ethereals, the Aquatoids, the Micronoids. Humanity has faced them all, and come out stronger. The Humans have left their world, exploring the stars, their technology built on Alien corpses. How will they react when they meet a peaceful society, one that is both advanced and primitive? ABANDONED, REWRITE IS UP UNDER THE TITLE 'THE HUMAN WAR!
Rated: T - English - Sci-Fi/Adventure - Chapters: 17 - Words: 52,325 - Reviews: 343 - Favs: 791 - Follows: 897 - Updated: 3/29/2016 - Published: 5/11/2014 - OC
XCOM: Mass Effect by Potatofanfiction reviews
Humanity has successfully destroyed ADVENT and the Elders. As humanity rejoices, the newly formed Union looks to the stars. It is unavoidable, then, that the Union, newly born from the embers of conflict would eventually meet with the Citadel.
Rated: T - English - Sci-Fi - Chapters: 2 - Words: 5,959 - Reviews: 45 - Favs: 138 - Follows: 213 - Updated: 3/16/2016 - Published: 3/10/2016
Mass Effect: X-Com Theory: Project Shanxi by timedraven117 reviews
It has been over a century since the Ethereal Invasion and the Equis First Contact War. Humanity has learned to accept their former foes, and their former victims. But the threat has always remained, "The greater foe" promised by the UberEthereal. Now it is the year 2157, near the Shaanxi system the Relay War shall begin with a galactic order that has stood for over 2,000 years.
Rated: T - English - Sci-Fi/Supernatural - Chapters: 11 - Words: 54,285 - Reviews: 78 - Favs: 251 - Follows: 311 - Updated: 11/10/2015 - Published: 5/8/2015 - Admiral Hackett, Councilor Tevos, Primarch Adrien Victus
A Confederation, A Citadel, and a Commander by Tabac Iberez reviews
nuXCOM/ME When LTC Shepard is called back to duty after admin leave, he doesn't expect anything serious. Certainly not an assignment to Citadel space, his own independent command, or discovering that the diffrence between geting told something and learning about it are as different as cake and pie. Between inter-species screwups and politicos at home, things are gonna get hairy.
Rated: T - English - Sci-Fi/Adventure - Chapters: 5 - Words: 9,196 - Reviews: 17 - Favs: 36 - Follows: 65 - Updated: 11/2/2015 - Published: 8/14/2015
Re-activation by skyfire777 reviews
After the war, XCOM was reduced to conspiracy theories and urban myths. They did not exist in any shape or form. But they were far from gone. Now, after 50 years of rebuilding, humanity faces yet another threat. Now, after 50 years of preparations, XCOM stands ready to face that threat. Covert!XCOM. Rating subject to change
Rated: T - English - Sci-Fi/Suspense - Chapters: 5 - Words: 9,696 - Reviews: 22 - Favs: 87 - Follows: 157 - Updated: 10/11/2015 - Published: 4/18/2015
The Technological Assimilators by Knight in Blackest Armor reviews
With the technologies of several alien races at its disposal, humanity had undergone a technological revolution. It advanced at such a rapid pace, far exceeding many expectations. Soon however, the humans learned that they shared their galaxy with yet another group of sentient alien life, but to mankind's horror and confusion, these aliens were not the sort they expected at all.
Rated: T - English - Sci-Fi - Chapters: 5 - Words: 147,111 - Reviews: 249 - Favs: 891 - Follows: 1,177 - Updated: 9/5/2015 - Published: 3/20/2014
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