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XCOM: The Avatar by Archwar reviews
As the Grimm attack Vale, a new force suddenly appeared and invades. Ruby Rose attempts to defeat the invaders and succeeds to an extent, but is knocked out by a lucky blow. She is then taken prisoner and imprisoned on ADVENT's earth. Now without much support, she must find out what has happened to Remnant before the Avatar Project is completed.
Crossover - X-Com & RWBY - Rated: T - English - Chapters: 1 - Words: 2,661 - Reviews: 1 - Favs: 4 - Follows: 8 - Published: 2/5
X-Com Into Darkness by deathwing17 reviews
After an information gathering mission in China, The leaders of X-Com learn that something strange is going on in Japan. They send a team in to investigate only for them to find something more disturbing than they originally feared.
Crossover - X-Com & Brynhildr in the Darkness/極黒のブリュンヒルデ - Rated: T - English - Sci-Fi/Horror - Chapters: 7 - Words: 40,428 - Reviews: 17 - Favs: 27 - Follows: 32 - Updated: 1/28 - Published: 8/12/2014
Family Reunion by Afalstein
In the wake of the Secret Invasion of 1962, two estranged family members meet at a diner. One's on her way out of the espionage business, the other has just gotten dragged back in, but they're both very interested in the future.
Crossover - X-Com & Agent Carter - Rated: K+ - English - Friendship - Chapters: 1 - Words: 1,219 - Published: 1/18 - P. Carter - Complete
Xcom: Human 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. Two storms will collide, destruction will be everywhere, and I can only hope this time it will be enough. COVER ART NEEDED!
Crossover - X-Com & Mass Effect - Rated: T - English - Adventure/Sci-Fi - Chapters: 4 - Words: 13,266 - Reviews: 57 - Favs: 111 - Follows: 145 - Updated: 1/18 - Published: 11/28/2015
Operation Angry Gods by adipose1913 reviews
When a UFO crashes near Camp Half-Blood, Percy, Annabeth, and the rest of the seven are thrown into a war with creatures even the gods are afraid of. T for mild violence and swearing.
Crossover - X-Com & Percy Jackson and the Olympians - Rated: T - English - Sci-Fi/Adventure - Chapters: 8 - Words: 21,775 - Reviews: 8 - Favs: 5 - Follows: 16 - Updated: 1/17 - Published: 9/26/2015
Before we take back by laynewarner10 reviews
7 years before 2035, the children of XCOM, Remnant, RvB, CP and Korra comes together to help Brandford rebuild XCOM. The first four chapters tell you about the children in the story and the parents that had them.
Crossover - X-Com & RWBY - Rated: T - English - Adventure/Hurt/Comfort - Chapters: 7 - Words: 4,367 - Reviews: 2 - Updated: 1/16 - Published: 11/21/2015 - Weiss Schnee, Adam Taurus, Penny
Ferris by Jonn Wood reviews
A geek ends up in the XCOM universe. Good News: He's just the Chief Engineer's personal assistant. Bad News: The Chief Engineer is Tony Stark.
Crossover - X-Com & Ironman - Rated: T - English - Sci-Fi/Drama - Chapters: 27 - Words: 104,184 - Reviews: 37 - Favs: 78 - Follows: 92 - Updated: 1/9 - Published: 1/8/2014 - A. E. Stark/Tony
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, SEE ENCLOSED NOTICE FOR DETAILS ABOUT REWRITE!
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Adventure - Chapters: 16 - Words: 52,292 - Reviews: 317 - Favs: 673 - Follows: 835 - Updated: 12/30/2015 - Published: 5/11/2014 - OC
Vigilance in the Shadows by tatantyler reviews
The Witches are, and have always been, humanity's counter to the Neuroi. But when a new threat that surpasses even the power of the Witches rises alongside the ongoing Neuroi invasion, one group stands against the coming storm. Vigilant and confident, they are the 115th Experimental Combat Unit: X-COM.
Crossover - X-Com & Strike Witches - Rated: T - English - Sci-Fi/Drama - Chapters: 6 - Words: 33,265 - Reviews: 12 - Favs: 11 - Follows: 17 - Updated: 12/30/2015 - Published: 11/24/2015 - Yoshika M.
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!
Crossover - X-Com & Mass Effect - Rated: T - English - Adventure/Sci-Fi - Chapters: 5 - Words: 20,119 - Reviews: 40 - Favs: 111 - Follows: 211 - Updated: 12/26/2015 - Published: 4/29/2015 - [Shepard (F), Garrus V.]
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...
Crossover - X-Com & Mass Effect - Rated: T - English - Humor/Sci-Fi - Chapters: 24 - Words: 240,217 - Reviews: 767 - Favs: 1,938 - Follows: 2,299 - Updated: 12/25/2015 - Published: 7/19/2014 - U. Wrex, Daro'Xen, Shepard (F), OC
Nostrom Custodimus a Tenabris, We Watch From the Shadows by Seras is love reviews
After the Anglo-American Bio Terrorism Incident, World Leaders decided that the UN was not strong enough to maintain peace. The most powerful nations of the Security Council met in secret to discuss plans for a response unit capable of detecting and preventing future incidents. An unexpected threat from beyond Earth places this unit in league with the shadowy Hellsing organization.
Crossover - X-Com & Hellsing - Rated: T - English - Supernatural/Sci-Fi - Chapters: 9 - Words: 11,745 - Reviews: 12 - Favs: 29 - Follows: 43 - Updated: 12/19/2015 - Published: 7/20/2015 - Integra, Seras, OC
Enemy of the Lost by baynard reviews
Magical folks had kept themselves out of the business of the muggle world, however an enemy from the stars that threatens all of humanity is something even they cannot hide from for long. Will a young child soldier trapped in an unending war against overwhelming odds be able to rise up to save both worlds? Or will he like so many before him be swallowed by the fires of war?
Crossover - Harry Potter & X-Com - Rated: T - English - Adventure - Chapters: 2 - Words: 5,037 - Reviews: 10 - Favs: 45 - Follows: 71 - Updated: 12/19/2015 - Published: 12/5/2015 - Harry P., James P., Lily Evans P.
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Supernatural - Chapters: 3 - Words: 14,036 - Reviews: 20 - Favs: 56 - Follows: 90 - Updated: 12/3/2015 - Published: 11/10/2015
XCOM: A soldier reborn (Cancelled) by frigginnope reviews
Story is cancelled, anyone who's willing to take it over is welcome to.
Crossover - X-Com & RWBY - Rated: T - English - Adventure/Sci-Fi - Chapters: 1 - Words: 2,720 - Reviews: 3 - Favs: 8 - Follows: 12 - Published: 11/20/2015 - Team RWBY
The Ragnarok Protocol by Brian01 reviews
It is the 41st Millennium. Forget the power of technology and science, for so much has been forgotten, never to be re-learned. Forget the promise of progress and understanding, for in the grim dark future there is only war. There is no peace amongst the stars, only an eternity of carnage and slaughter, and the laughter of thirsting gods. But what if something changed...
Crossover - X-Com & Warhammer - Rated: T - English - Sci-Fi - Chapters: 2 - Words: 1,531 - Reviews: 12 - Favs: 20 - Follows: 35 - Updated: 11/20/2015 - Published: 11/13/2015
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Supernatural - Chapters: 11 - Words: 54,285 - Reviews: 55 - Favs: 184 - Follows: 236 - Updated: 11/10/2015 - Published: 5/8/2015 - Admiral Hackett, Councilor Tevos, Primarch Adrien Victus
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Adventure - Chapters: 16 - Words: 152,262 - Reviews: 379 - Favs: 738 - Follows: 813 - Updated: 11/5/2015 - Published: 9/2/2014
Stargate Program: Extraterrestrial Combat Unit by GreyWardenN7 reviews
Follow Lt Col Michael Hunter, a British soldier from the Extraterrestrial Combat Unit, as he assists the flagship team SG-1 in their journey across the galaxy against the Goa'uld, Sectoids and more.
Crossover - Stargate: SG-1 & X-Com - Rated: T - English - Adventure/Sci-Fi - Chapters: 1 - Words: 2,019 - Reviews: 4 - Favs: 6 - Follows: 13 - Published: 11/4/2015 - S. Carter, OC
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Adventure - Chapters: 5 - Words: 9,196 - Reviews: 15 - Favs: 32 - Follows: 59 - 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
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Suspense - Chapters: 5 - Words: 9,696 - Reviews: 19 - Favs: 78 - Follows: 144 - Updated: 10/11/2015 - Published: 4/18/2015
RWBY:Psion Unleashed by EliteOp reviews
The Volunteer was considered KIA aboard the mothership, his lifesigns disappearing. Noone knows where he went but him. He needs to set up, find allies and enjoy his new life while he can, as dark things are coming.
Crossover - X-Com & RWBY - Rated: T - English - Romance/Humor - Chapters: 10 - Words: 13,356 - Reviews: 11 - Favs: 13 - Follows: 19 - Updated: 9/13/2015 - Published: 6/9/2015 - [OC, Yang Xiao Long] Team RWBY, Team JNPR
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi - Chapters: 5 - Words: 138,856 - Reviews: 203 - Favs: 660 - Follows: 905 - Updated: 9/5/2015 - Published: 3/20/2014
Finally, A Death Prevented by Urza3142 reviews
For a medieval universe, there aren't a lot of people around to save Elodie from certain death. Things were getting so out of hand that the powers that be decided to send another universe's heroes to mix things up. Rated T for language. One Shot. All XCOM soldiers are OC.
Crossover - X-Com & Long Live the Queen - Rated: T - English - Sci-Fi - Chapters: 1 - Words: 5,174 - Reviews: 1 - Favs: 1 - Follows: 3 - Published: 8/10/2015 - Elodie - Complete
X-marks the Steven by The Cowardly Christian 'du911 reviews
Post-Jailbreak AU! Upset with the recent invasion, X-com mobilizes on Beach City...Try not to blow up Steven guys! Inspired by Psykotic Addiction and Hotpoint!
Crossover - X-Com & Steven Universe - Rated: T - English - Supernatural/Sci-Fi - Chapters: 1 - Words: 253 - Reviews: 2 - Favs: 3 - Follows: 4 - Published: 8/5/2015 - Steven U.
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