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Terra s Destiny: A prelude to War by GeneralAllenWalker reviews
Jack O'Neill thought he had done enough to earn a retirement. Fighting the russians in east germany, killing an alien god in a distant star system thousands of light years away, being a productive member of the Colorado Springs golf club, all very laudable things, if he allowed himself the compliment. Sadly, it seems, the universe had other ideas as Earth faces an Enemy Unknown
Crossover - Stargate: SG-1 & X-Com - Rated: T - English - Sci-Fi/Adventure - Chapters: 5 - Words: 14,978 - Reviews: 14 - Favs: 15 - Follows: 28 - Updated: 5/1 - Published: 12/15/2023 - S. Carter, J. O'Neill
BRWL: A Tale of Aura and Aliens by GreenTheRyno reviews
Aliens, cat-people, interdimensional travelers, soul magic... all used to be the realm of science fantasy. Now the world has to deal with all these fantastical beings and things. Those last three will affect no family more than the Xiao Longs, an average but broken family in rural Minnesota. Follow them and their friends as they deal with everything the world has to throw at them
Crossover - X-Com & RWBY - Rated: M - English - Sci-Fi - Chapters: 15 - Words: 87,325 - Reviews: 9 - Favs: 25 - Follows: 33 - Updated: 4/26 - Published: 2/12 - [Yang X.L., Jaune A.] Ruby R., Blake B.
Wild Hearts by Garriso
A squad of hardened soldiers, one high-tech air-carrier, and ten thousand missed 99% shots! That's XCOM baby! After an op gone wrong in Hong Kong, the Lagoon crew is forced to partner up with the resistance to end the Elders once and for all.
Crossover - X-Com & Black Lagoon - Rated: M - English - Adventure/Romance - Chapters: 1 - Words: 5,731 - Favs: 1 - Follows: 2 - Published: 4/18 - [Revy, Rock] OC
Eagles Over Earth by CopperStandard reviews
In response to mysterious alien incursions, the Global Defense Initiative activates the XCOM Project, bringing together their finest leaders, scientists, and soldiers to combat this new threat by all means necessary. But in a world already succumbing to Tiberium and old enemies lurking in the shadows, it will take a supreme effort from XCOM to merely survive, let alone win.
Crossover - X-Com & Command & Conquer - Rated: M - English - Sci-Fi - Chapters: 17 - Words: 67,923 - Reviews: 116 - Favs: 63 - Follows: 66 - Updated: 3/8 - Published: 6/21/2021 - Dr. Vahlen, M. McNeil, OC
XCOM Justice by Blackace12 reviews
After a long war with Advent and an invasion even the Elder's fear, with the final order of the Commander he sacrifices himself not only to save the world but the universe as well only to find himself in another earth were X-com doesn't exist and the world is filled with Superhero aliens and Villans
Crossover - X-Com & Young Justice - Rated: M - English - Adventure/Sci-Fi - Chapters: 22 - Words: 186,730 - Reviews: 133 - Favs: 314 - Follows: 376 - Updated: 2/22 - Published: 12/31/2019
Code Geass: The Grey Chessmen by Generatedname reviews
An unknown enemy encountered during a Refrain bust leads the newly formed Black Knights to a discovery that warns of a coming global catastrophe. The question is, will they be ready in time to face it?
Crossover - X-Com & Code Geass - Rated: T - English - Sci-Fi/Drama - Chapters: 8 - Words: 169,114 - Reviews: 84 - Favs: 139 - Follows: 171 - Updated: 2/18 - Published: 7/21/2023 - Lelouch L.
BRWL: Ally Unknown (old version, rewrite is posted) by GreenTheRyno reviews
They called it the most important war in Human history; one we were not allowed to lose. Our first and last line of defense stands alone against the onslaught, yet victory may be delivered by the very hands that sought to destroy us. Vigilo Confido, Curatrix Ab Alibi.
Crossover - X-Com & RWBY - Rated: M - English - Sci-Fi/Fantasy - Chapters: 9 - Words: 51,270 - Reviews: 17 - Favs: 25 - Follows: 32 - Updated: 2/12 - Published: 11/8/2020 - EXALT, Blake B., Penny P., Team RWBY
XCOM And Gears: The Resistance Rising by Deviltown v3 reviews
A crossover of everyone's favorite games. The COG and XCOM work together to take out the Ethereals and their alien army. Things seem to be going as usual... Until the truth slowly starts to unravel after a Reaper saves the Gears from Hunter. Someone thinks she's.. Familiar. Rated M for the harsh language and gore. !"GEARS OF WAR BELONGS TO COALITION AND XCOM BELONGS TO FIRAXIS."!
Crossover - Gears of War & X-Com - Rated: M - English - Angst/Sci-Fi - Chapters: 1 - Words: 1,368 - Reviews: 1 - Favs: 1 - Follows: 1 - Published: 1/12 - D. Baird, Dominic S., Marcus F., Bradford
DCOM: Afterlife by ImThinking reviews
A crossover between XCOM 2 and Girls Frontline. Complete Spec Ops missions to reclaim the Earth from the Alien Occupiers and get laid by hot raifus along the way.
Crossover - X-Com & Girls' Frontline/少女前线 - Rated: M - English - Sci-Fi/Adventure - Chapters: 5 - Words: 195,784 - Reviews: 2 - Favs: 28 - Follows: 31 - Updated: 1/1 - Published: 10/21/2022 - Dr. Tygan, Firebrand, OC, Kalina
The Rising Phoenix (XCOM Multi-Crossover) by CommanderAsaru reviews
In a universe filled with ancient conspiracies, vast alien empires, demented cultists, and eldritch horrors, XCOM tries to carry out its duty: survive, adapt, and win.
Crossover - X-Com & X-overs - Rated: M - English - Sci-Fi/Horror - Chapters: 4 - Words: 11,031 - Reviews: 2 - Favs: 9 - Follows: 12 - Updated: 12/30/2023 - Published: 12/19/2023 - Bradford, Dr. Vahlen, R. Shen, Van Doorn
The Star Union by ImageViewer reviews
In the Year 2015, Earth was attacked by an unknown Alien Empire. With X-com they fought the alien menace again and again, overcoming the Odds and Forging a new Empire comprised of the former enemies enslaved to the Elder's will. Now forged into an empire the likes of which the galaxy hasn't seen, they take their first steps into the great Unknown. Major Crossovers and OCs.
Crossover - Mass Effect & X-Com - Rated: M - English - Sci-Fi/Adventure - Chapters: 5 - Words: 48,483 - Reviews: 46 - Favs: 372 - Follows: 513 - Updated: 12/28/2023 - Published: 7/17/2021 - Liara T'Soni, Tali'Zorah, Shepard, OC
Volunteers (XCOM X MCU) by CommanderAsaru reviews
Annette Durand expected to die when she threw the Temple Ship into the sky. Instead, she is transported into the Marvel Cinematic Universe (MCU), a world teeming with superheroes, advanced technology, and cosmic threats. Grappling with the shock of being displaced to a world of fantastical abilities, Annette decides to do what she has always done: survive, adapt, and win.
Crossover - X-Com & Avengers - Rated: T - English - Sci-Fi/Adventure - Chapters: 3 - Words: 4,169 - Reviews: 6 - Favs: 22 - Follows: 39 - Updated: 12/26/2023 - Published: 12/19/2023 - Hawkeye/Clint B., Nick F., Agent Phil Coulson, Agent Maria Hill
A Dream of Terrors by Spearka reviews
Crossover between Game of Thrones and XCOM. As the Dead march south, a new and mysterious force from another world is poised to change Westeros forever.
Crossover - X-Com & Game of Thrones - Rated: M - English - Sci-Fi/Fantasy - Chapters: 6 - Words: 58,647 - Reviews: 23 - Favs: 65 - Follows: 105 - Updated: 10/22/2023 - Published: 6/16/2019
Xcom: Fire From Above by StalinWithDaSpoon reviews
XCOM is fighting a desperate fight. It lost the first contact war, and now it was struggiling in the war of resistance. Even with the Commander to lead them, they had made only minor progress in destabilizing the aliens regime. But this would change with a new factor being added to the battle, as what can only be described as Fire From Above.
Crossover - X-Com & Halo - Rated: T - English - Sci-Fi/Adventure - Chapters: 5 - Words: 12,309 - Reviews: 11 - Favs: 86 - Follows: 121 - Updated: 9/6/2023 - Published: 7/19/2023 - Bradford, J. Cutter, E. Anders, Jerome-092
Guardian Gun by BiazarKaiser reviews
Sometimes, to get something done, you need to be willing to sacrifice something for the mission, like your humanity and someone's free will. There are some assholes needing a lesson and these will become common thing for me being an Ethereal and a reincarnated. SI, XCOM/Shield Hero, key people may die.
Crossover - Rising of the Shield Hero/盾の勇者の成り上がり & X-Com - Rated: M - English - Hurt/Comfort - Chapters: 2 - Words: 4,577 - Reviews: 1 - Favs: 20 - Follows: 21 - Updated: 7/20/2023 - Published: 3/9/2023 - Bradford, OC, Naofumi I., Shadow
Resistance by pokeman1280 reviews
The Traitor is dead. Salem is dead. Ruby thought she could live in at least temporary retirement, but the universe had other plans. Stripped from her home, away from those she loves the most, she is forced to fight for a world foreign to her. Few others are in her position The only way for everyone get back to their homes, help X-COM win their war.
Crossover - X-Com & RWBY - Rated: T - English - Sci-Fi - Chapters: 31 - Words: 177,975 - Reviews: 91 - Favs: 132 - Follows: 165 - Updated: 6/12/2023 - Published: 12/9/2019 - Bradford, Ruby R.
Because Of The War by HistoricalHijinks reviews
August 31st, 2010, 19:00 hours, Brockton Bay, Approximately Fifteen Minutes from Brockton Bay Cinemas. The precise time and place that Taylor Hebert was fatally wounded whilst caught in the crossfire between the ABB and the E88. The precise time and place that the Queen Administrator, suborned by the Earth-born Ethereal Asaru, made Taylor The Commander of XCOM.
Crossover - X-Com & Worm - Rated: M - English - Sci-Fi/Romance - Chapters: 16 - Words: 85,835 - Reviews: 334 - Favs: 1,982 - Follows: 2,466 - Updated: 5/22/2023 - Published: 9/19/2017 - [Skitter, Panacea] [Danny H., Miss Militia]
Worm - UFO Defense by Seawolf321 reviews
Earth Bet already has many truly monstrous threats: the Endbringers, the Slaughterhouse 9, Nilbog, the three Blasphemies. the Machine Army, the Fairie Queen among many others. But now Earth Bet has to face a new enemy...an Enemy Unknown.
Crossover - X-Com & Worm - Rated: T - English - Chapters: 3 - Words: 13,674 - Reviews: 7 - Favs: 26 - Follows: 29 - Updated: 2/28/2023 - Published: 2/26/2023 - Bradford, OC, Panacea, Miss Militia
X-COM: Enemy Transformed by Wreck - GD reviews
In 1973 a Decepticon warship was shot down on Iceland and after a short conflict ended with a massive nuclear explosion on Iceland rendering a large chunk of the Island a restricted zone. After a massive cover-up operation, the most powerful individuals on this Planet pulled together a vast amount of resources into project X-COM. [Under Rewrite]
Crossover - Transformers/Beast Wars & X-Com - Rated: M - English - Sci-Fi/Adventure - Chapters: 5 - Words: 12,730 - Reviews: 10 - Favs: 26 - Follows: 38 - Updated: 12/15/2022 - Published: 2/26/2022 - Bradford, Dr. Vahlen, R. Shen
ИксЗВКом: Зеркальное отражение by bbor1974
Перевод XSGCOM: Goa'uld Defence(Mirror Image) Оригинал: tthf .me/86hU
Crossover - Stargate: SG-1 & X-Com - Rated: T - Russian - Adventure - Chapters: 38 - Words: 194,833 - Favs: 5 - Follows: 4 - Updated: 11/27/2022 - Published: 3/10/2021
Eva com by Subject idea reviews
The year is now 2015, the first angel Adam and his children never got the chance to waken and the evangelion project was ended. The world was left in its normal state but a new threat comes for humanity from the cold and endless reaches of space. Shinji Ikari now finds himself in the middle of this conflict, fighting with Xcom against the endless might of the ethereal aliens.
Crossover - Evangelion & X-Com - Rated: M - English - Sci-Fi/Drama - Chapters: 2 - Words: 4,410 - Reviews: 2 - Favs: 3 - Follows: 5 - Updated: 11/27/2022 - Published: 10/18/2022 - Shinji I., Asuka L. S., Misato K., Mana K.
The Volunteers by Tekkonair
Weiss Schnee, soldier in the X-COM project, volunteers for the MEC trooper project after suffering crippling injuries on a mission. Her girlfriends, Yang and Pyrrha, help her recover from the emotional toll, eventually volunteering for other projects intended to help fight the alien menace Tender, loving sex and emotional reinforcement inside. Also XCOM fight scenes, why not?
Crossover - X-Com & RWBY - Rated: M - English - Romance/Hurt/Comfort - Chapters: 3 - Words: 11,989 - Favs: 4 - Follows: 4 - Updated: 10/7/2022 - Published: 9/23/2022 - [Weiss S., Pyrrha N., Yang X.L.]
Operation Obsidian Paladin by Flameal15k reviews
An exiled prince and princess find themselves drawn into a shadow war for the fate of Earth. But will this hidden conflict soon become overt? And are aliens the only enemies they will face?
Crossover - X-Com & Code Geass - Rated: T - English - Sci-Fi/Romance - Chapters: 1 - Words: 1,241 - Reviews: 3 - Favs: 8 - Follows: 15 - Published: 9/30/2022 - Bradford, Big Sky, Lelouch L., Kallen S.
Quantum Trouble by Laigron reviews
When NID managed to convince President not to destroy quantum mirror its send to P8R-553 to establish research outpost and to properly study mirror. . Few month after properly establishing outpost and studying the mirror. All contact was lost. SG-1 prepares for recon and subsequent rescue mission.
Crossover - Stargate: SG-1 & X-Com - Rated: T - English - Sci-Fi - Chapters: 1 - Words: 1,252 - Reviews: 2 - Favs: 12 - Follows: 21 - Published: 8/23/2022 - D. Jackson, J. O'Neill, OC, Warlock
Bugs, Guns, and Conflagrations (UP FOR ADOPTION) by Defective Viper reviews
After defeating the Radiance, little Ghost thinks they can die in peace alongside their siblings but fate has other plans for them. •This story is currently up for adoption. DM me on Discord if you want to Adopt it: Protonic Protogen#9946
Crossover - X-Com & Hollow Knight - Rated: T - English - Sci-Fi - Chapters: 2 - Words: 3,746 - Reviews: 3 - Favs: 12 - Follows: 16 - Published: 4/5/2022
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