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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: 43 - Words: 180,695 - Reviews: 42 - Favs: 113 - Follows: 131 - Updated: 6/22 - Published: 1/8/2014 - A. E. Stark/Tony, OC
Warframe: The Invisible War by gh0st3 reviews
It's been 10 years since Ballas took Lotus away from 005. She never stops her searching until she gave her idea to Ordis. From what she is expected to enter a new kind of war. She has many questions with her own mind. Will she play her part as a lone soldier or join with Xcom? Perhaps will she use her P.O.T.A.T.O. from Darvo's idea? *Spoilers from Second Dream and War Within*
Crossover - X-Com & Warframe - Rated: T - English - Sci-Fi/Adventure - Chapters: 2 - Words: 4,225 - Reviews: 4 - Favs: 6 - Follows: 13 - Updated: 6/15 - Published: 5/24
Warframe Contact by NamThunder reviews
Two XCOM operatives were kidnapped by the Grineer, and then rescued by the Tenno. Perhaps XCOM might gain a valuable ally
Crossover - X-Com & Warframe - Rated: T - English - Chapters: 2 - Words: 3,487 - Reviews: 1 - Favs: 5 - Follows: 7 - Updated: 6/14 - Published: 6/13
Alienation by a-mild-looking-sky reviews
CIA agent William Carter never bargained on combatting an alien invasion. He certainly never bargained on combatting two of them. [The Bureau: XCOM Declassified/Alien crossover]
Crossover - Aliens/Predator & X-Com - Rated: T - English - Sci-Fi/Horror - Chapters: 5 - Words: 21,282 - Reviews: 15 - Favs: 3 - Follows: 2 - Updated: 6/10 - Published: 3/1 - Alien/Xenomorph
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi - Chapters: 13 - Words: 138,222 - Reviews: 592 - Favs: 1,436 - Follows: 1,965 - Updated: 5/30 - Published: 3/29/2016
The Xcom Familiar by mytigerrage reviews
The Volunteer was KIA, or so people believed. In reality, he was summoned by a pint-haired brat named Louise La Valliere. This will not end well. Spoilers for Xcom: Enemy Within. My first fanfiction, so input is well-appreciated. Delayed for a week or two.
Crossover - X-Com & Familiar of Zero - Rated: T - English - Chapters: 4 - Words: 1,297 - Reviews: 2 - Favs: 2 - Follows: 1 - Updated: 5/29 - Published: 5/15
Twenty Years Late by A Very Thirsty Megalomaniac reviews
It's hard for the Ethereals to invade when someone else got there first.
Crossover - X-Com & Half-Life - Rated: T - English - Sci-Fi/Adventure - Chapters: 6 - Words: 28,971 - Reviews: 10 - Favs: 19 - Follows: 20 - Updated: 5/28 - Published: 5/14 - Bradford, A. Shephard, Barney C., The Combine
Avatar of Liberty by NamThunder reviews
The Elder's last hope, the Exodus, was launched during XCOM's final assault on the underwater fortress. The last Ethereal and Avatar, designated as Noah, had to led the crew of the Exodus to find new allies. But they did not expect who and what they will meet in this Kropulu Sector. ATTENTION: UNDER REWRITING
Crossover - StarCraft & X-Com - Rated: T - English - Sci-Fi/Adventure - Chapters: 10 - Words: 19,501 - Reviews: 31 - Favs: 30 - Follows: 35 - Updated: 5/13 - Published: 3/1 - James R., Terran, OC
New Haven by WDO345 reviews
One/Shot. Crossover idea. Earth has died and XCOM has transported the survivors onto Westeros. Up for Adoption.
Crossover - X-Com & Game of Thrones - Rated: T - English - Chapters: 2 - Words: 8,736 - Reviews: 20 - Favs: 38 - Follows: 52 - Updated: 4/18 - Published: 7/9/2017
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, ever-going, while a vast, unknown Galactic Civilization lives right upon its borders, a new friend, or possible foe.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi/Adventure - Chapters: 5 - Words: 3,939 - Reviews: 6 - Favs: 33 - Follows: 58 - Updated: 4/5 - Published: 3/25
To Fight for Humanity by Nanocowie reviews
They all doubted him, his parents, his colleagues, but they forgot exactly who was in charge here. Harry joined the resistance group, the Reapers, at the young age of 9, learning their ways and getting back at the world who shunned him so. But one fateful day he was set to go on a mission, a peace rendezvous with their rivals the Skirmishers. One which would change his life forever
Crossover - Harry Potter & X-Com - Rated: T - English - Romance - Chapters: 3 - Words: 27,384 - Reviews: 7 - Favs: 58 - Follows: 73 - Updated: 3/29 - Published: 2/2 - Harry P., OC
War for a Heaven (XCOMNeon Genesis Evangelion) by Centralion reviews
In the year of 2015, humanity finds itself facing a war for survival on two fronts. On one end, attacks from another world by cold and strange intelligences, on the other, strange unstoppable monsters that brush aside all defenses. Two organizations, each created to combat one of these threats, stand together in an uneasy alliance, and, for Written in Partnership With Erttheking.
Crossover - Evangelion & X-Com - Rated: T - English - Sci-Fi - Chapters: 1 - Words: 13,398 - Reviews: 5 - Favs: 8 - Follows: 13 - Published: 3/6
Starlit Revolution by Fun Pak 64 reviews
The invading force has taken down XCOM, and convinced the Monarchs of Pop Star to surrender the planet to them and ADVENT. XCOM's Commander has been captured by the invaders. The Hero of the Stars vanished after the destruction of XCOM HQ. That was thirty years ago. Now, the reborn XCOM must rescue their Commander, find the Hero and overthrow ADVENT. It all starts with this.
Crossover - X-Com & Kirby - Rated: K+ - English - Sci-Fi/Adventure - Chapters: 1 - Words: 1,198 - Reviews: 2 - Published: 2/25
Operation: Brooding Tome by Luke Danger
Sometimes, the Commander initiates some quite questionable missions. And when a Covert Action allowed an opening for only two XCOM operatives to go after a general, the Commander's choice of operatives had to pull off a textbook suicide mission. So not the drama for Team Possible, right?
Crossover - X-Com & Kim Possible - Rated: T - English - Sci-Fi/Adventure - Chapters: 2 - Words: 9,980 - Favs: 3 - Follows: 4 - Updated: 2/2 - Published: 1/30 - [Kim P., Ron S.] Bradford
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.
Crossover - X-Com & Mass Effect - Rated: T - English - Sci-Fi - Chapters: 1 - Words: 6,044 - Reviews: 3 - Favs: 68 - Follows: 83 - Published: 1/9
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: 43 - Words: 387,570 - Reviews: 1333 - Favs: 3,071 - Follows: 3,602 - Updated: 1/2 - Published: 7/19/2014 - U. Wrex, Daro'Xen, Shepard (F), OC
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: 10 - Words: 54,098 - Reviews: 24 - Favs: 48 - Follows: 50 - Updated: 12/27/2017 - Published: 8/12/2014
War on Remnant (Xcom 2RWBY Crossover Challenge) by Dungeon Wyrm reviews
The people of Remnant have fought the Grimm since the beginning, and barely manage to thrive. So what would happen if the suddenly find out that they are not alone in the universe? And that some of these visitors don't come in peace?
Crossover - X-Com & RWBY - Rated: T - English - Chapters: 1 - Words: 249 - Reviews: 1 - Published: 12/10/2017
XCOM: Volunteer Raptor Trainer by Dr1ft3r0I reviews
All the Volunteer wanted after getting sucked into a psionic portal twice was an easy job. Raising genetically engineered Utahraptors for Jurassic World wasn't quite what he had in mind.
Crossover - X-Com & Jurassic Park - Rated: T - English - Sci-Fi - Chapters: 3 - Words: 9,607 - Reviews: 16 - Favs: 39 - Follows: 73 - Updated: 12/8/2017 - Published: 5/4/2017
XCOM: Pony Unknown by PrinceBoss233 reviews
Alien attacks are being launched in Equestria and Earth by the same alien race named the Elders. Maverick, his wife Twilight and their friends go to Earth to find help but what they don't know is that the aliens are also attacking there, but with more force. {Sorry for the terrible summary, it's my first time writing on this site so I'm still new to this :p}
Crossover - My Little Pony & X-Com - Rated: T - English - Adventure/Sci-Fi - Chapters: 5 - Words: 10,513 - Reviews: 1 - Favs: 3 - Follows: 4 - Updated: 11/7/2017 - Published: 9/17/2017 - Rainbow Dash, OC, EXALT, Bradford
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: 4 - Words: 11,536 - Reviews: 24 - Favs: 108 - Follows: 162 - Updated: 10/13/2017 - Published: 12/5/2015 - Harry P., James P., Lily Evans P.
Gate - Thus The Ethereals Find A New Planet by Jeggetts reviews
A Gate opens up in Japan. The only problem is, the ones who already conquered earth, are still here. One-Shot.
Crossover - X-Com & Gate - Jietai Kare no Chi nite, Kaku Tatakeri - Rated: T - English - Sci-Fi/Fantasy - Chapters: 1 - Words: 8,201 - Reviews: 9 - Favs: 35 - Follows: 25 - Published: 9/7/2017 - Complete
Highschool SCAN by JadedJackal reviews
The people of the Supernatural World were being to noisy and ended up on the Council's Watch List. To deal with this new genre of threat they have founded S.C.A.N. X-COM deals with aliens, while S.C.A.N deals with spirits, demons and etc. note: X-COM has a small presence in this story so don't think aliens will be in the mix.
Crossover - X-Com & High School DxD/ハイスクールD×D - Rated: T - English - Adventure/Supernatural - Chapters: 1 - Words: 969 - Reviews: 1 - Favs: 8 - Follows: 6 - Published: 8/6/2017
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. Hiatus*
Crossover - X-Com & Mass Effect - Rated: T - English - Suspense/Adventure - Chapters: 11 - Words: 39,880 - Reviews: 125 - Favs: 257 - Follows: 335 - Updated: 8/3/2017 - Published: 11/28/2015
Ambassador by BrightestDarkness reviews
Into the disfigured Sol system, the races of the Milky Way flees from the Reaper onslaught nipping at their heels. Forced into a grudging coexistence with a battle-worn humanity, the many races now hiding within the Sol barricade must find a new beginning and move beyond the cataclysms of history past for the sake of another tomorrow. Mass Effect/XCOM/Blackadder/Mega Crossover
Crossover - X-Com & Mass Effect - Rated: T - English - Humor/Sci-Fi - Chapters: 5 - Words: 18,524 - Reviews: 29 - Favs: 85 - Follows: 105 - Updated: 7/22/2017 - Published: 6/20/2017 - Dr. Vahlen, Van Doorn, Shepard (F)
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