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Strange and Marvelous accounts and paranormal files from the Bureau by Jyggilag reviews
In a distant far-off alternate world under constant threat by rampant Altered World Events. There is only one agency capable of keeping the situation under control. These are some of the chronicles of its exploits.
Crossover - X-Com & Control - Rated: M - English - Mystery/Supernatural - Chapters: 1 - Words: 18,729 - Reviews: 3 - Favs: 6 - Follows: 9 - Published: 7/26/2021 - Bradford, Van Doorn, Jessie F., E. Pope
Chimera's Aug by MiffedMonkey reviews
Thirteen years after the events of Human Revolution, an aged Adam Jensen is invited to join Chimera Squad. His experience and augments being an invaluable asset to control. His presence may be all that stands between the city's success as a model for peaceful coexistence and total chaos. Rated M for blood and violence alongside sexual themes. Please read and review
Crossover - X-Com & Deus Ex - Rated: M - English - Sci-Fi/Crime - Chapters: 13 - Words: 18,126 - Reviews: 13 - Favs: 20 - Follows: 33 - Updated: 6/25/2021 - Published: 11/6/2020 - OC, Adam Jensen
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: 26 - Words: 132,147 - Reviews: 69 - Favs: 168 - Follows: 194 - Updated: 4/16/2021 - Published: 5/14/2018 - Bradford, A. Shephard, Barney C., The Combine
A Second Front by Slayerofsnails reviews
After being sucked in a portal years ago Taylor, now an X-Com operative faces a chance at her lost home while in the middle of a war for the continued existence of humanity.
Crossover - X-Com & Worm - Rated: M - English - Sci-Fi - Chapters: 8 - Words: 21,432 - Reviews: 21 - Favs: 105 - Follows: 156 - Updated: 4/14/2021 - Published: 3/25/2021
The Vigilant Knights by Unhacker the Laziest Bastard reviews
The Saderan Empire had prepared for everything that they could consider when they marched through the gate. Intent on transforming the primitive world into another territory. What they did not expect was that others had tried before. A GATE x XCOM Crossover
Crossover - X-Com & Gate - Jietai Kare no Chi nite, Kaku Tatakeri - Rated: T - English - Fantasy/Sci-Fi - Chapters: 2 - Words: 3,080 - Reviews: 6 - Favs: 45 - Follows: 90 - Updated: 2/2/2021 - Published: 1/15/2021 - OC, OC, Rose Knights, Third Recon
ACM: Enemigo Desconocido by VMCG93 reviews
Cuando los alienigenas vienen a Equestria con intenciones hostiles, solo un grupo podrá detenerlos. Agencia Cazadora de Monstruos va a incluir alienigenas en su lista de cacería. Y van a no solo salvar su mundo, si no, otro más. Averigüe como leyendo esta historia.
Crossover - X-Com & My Little Pony - Rated: T - Spanish - Sci-Fi/Suspense - Chapters: 187 - Words: 1,312,086 - Reviews: 235 - Favs: 13 - Follows: 13 - Updated: 1/15/2021 - Published: 8/12/2018 - Bradford, Princess Celestia, Sunset Shimmer, OC - Complete
Shattered Fate by Illuviar reviews
The year is 2175 and the galaxy is at peace. In the Terminus Systems, Battarian sponsored pirates gather, willing to test the resolve and capabilities of the System Alliance. At a X-COM facility, the last surviving soldier from the last war has been released from stasis, ready to be healed. Meanwhile the Ethereals plot in the shadows beyond the Relay Network and Nazara awakens...
Crossover - X-Com & Mass Effect - Rated: M - English - Sci-Fi/Adventure - Chapters: 30 - Words: 91,817 - Reviews: 96 - Favs: 383 - Follows: 495 - Updated: 12/30/2020 - Published: 2/3/2016
Strange people from a war-torn world by Narsauce reviews
The war for Earth is over, the Elders and Advent have been defeated. As Alpha Squad, the best XCom has, begins to settle into a new life of peace, their lives are thrown astray as a mission to find an old friend gets FUBAR. Now, thrown into a world new to them, they must adapt to survive... the high school classroom as teachers.
Crossover - X-Com & RWBY - Rated: T - English - Sci-Fi/Hurt/Comfort - Chapters: 20 - Words: 151,698 - Reviews: 30 - Favs: 137 - Follows: 188 - Updated: 12/17/2020 - Published: 9/25/2018 - Bradford, Summer R., Emerald S., Team RWBY
Puella Magi Lily Shen by edric2016underwood reviews
"Lily" Shen An-Yi is a child prodigy who has been the XCOM Chief Engineer since her father - Dr. Raymond Shen has gone because of the alien occupation. In a hopeless situation which XCOM is left decimated again and Earth is still controlled by the Elders through the puppet ADVENT Administration, Lily Shen makes a contract with an alien called Kyubey and became a Magical Girl.
Crossover - X-Com & Puella Magi Madoka Magica/魔法少女まどか★マギカ - Rated: T - English - Humor/Sci-Fi - Chapters: 2 - Words: 11,210 - Reviews: 2 - Favs: 3 - Follows: 3 - Updated: 12/1/2020 - Published: 9/8/2020
It Was Never Just About the Suit by ajpa reviews
In addition to the Ethereal Device, XCOM also recovered a device akin to a gateway/portal. Meanwhile, in a different universe, Prophet is caught the feedback reaction from destroying the Ceph wormhole.
Crossover - X-Com & Crysis - Rated: T - English - Adventure - Chapters: 5 - Words: 3,763 - Reviews: 7 - Favs: 24 - Follows: 37 - Updated: 11/9/2020 - Published: 3/19/2020
Contingency Plans across several Alternate Universes! by mpalmer89 reviews
The X-Com Troops deal with the actions of the Sectoids to save the Asgard Species from extinction while the Daleks invade the Stargate Universe against both sides!
Crossover - Stargate: SG-1 & X-Com - Rated: M - English - Adventure/Drama - Chapters: 608 - Words: 200,376 - Reviews: 21 - Favs: 21 - Follows: 19 - Updated: 10/30/2020 - Published: 10/17/2010
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.
Crossover - StarCraft & X-Com - Rated: T - English - Sci-Fi/Adventure - Chapters: 23 - Words: 43,291 - Reviews: 88 - Favs: 120 - Follows: 146 - Updated: 9/29/2020 - Published: 3/1/2018 - James R., Terran, OC
Gargoyles: UFO Defense by Stupid the Ork reviews
What happens when a part of Maggie's past comes searching for her? A part whose job is to wage war against superior alien invaders and their monsters? X-COM side combined with Xenonauts.
Crossover - Gargoyles & X-Com - Rated: T - English - Sci-Fi/Adventure - Chapters: 1 - Words: 1,021 - Reviews: 1 - Favs: 3 - Follows: 10 - Published: 9/23/2020 - [Maggie R., OC] Talon
XCOM:Land of Fantasy by UNSC Know Your Place reviews
The Alien Invasion is over, the world began to rebuild what was lost, peace is restored. Yet wary of the stars, the people of the world will know that their planet held secrets of its own than the stars above. XCOM will once again, dive to the unknown.
Crossover - X-Com & Touhou Project - Rated: T - English - Chapters: 3 - Words: 25,984 - Reviews: 26 - Favs: 48 - Follows: 57 - Updated: 9/19/2020 - Published: 4/16/2020
ИксЗВКом: Зеркальное отражение by testpilot24 reviews
Перевод XSGCOM: Mirror Image. Ссылка на оригинал: fanfiction .net /s/3631062/1/XSGCOM Mirror Image.
Crossover - Stargate: SG-1 & X-Com - Rated: T - Russian - Adventure - Chapters: 9 - Words: 41,383 - Reviews: 3 - Favs: 5 - Follows: 5 - Updated: 8/31/2020 - Published: 9/1/2011 - Complete
XCOM: Enemy Without by Redrover117 reviews
The year 2015 was when everything changed, when machines descended from the sky and rained death down on the Earth. They thought that we would be easy to conquer, to destroy, they were wrong. The XCOM Project has been officially activated. Good luck Commander.
Crossover - X-Com & Battlestar Galactica: 2003 - Rated: M - English - Chapters: 14 - Words: 27,571 - Reviews: 40 - Favs: 88 - Follows: 98 - Updated: 8/6/2020 - Published: 4/15/2020 - Complete
The War of Exaltation War of the Worlds XCOM by Praetus reviews
The world is undergoing unprecedented change. It is a time of progress, prosperity and blinding achievement, coupled with dire poverty and a world under pressure from internal struggles. So, no wonder everyone thought the chances of something coming from Mars were a million to one
Crossover - X-Com & War of the Worlds - Rated: T - English - Adventure/Drama - Chapters: 53 - Words: 200,339 - Reviews: 52 - Favs: 43 - Follows: 41 - Updated: 6/19/2020 - Published: 6/1/2019 - Bradford, Dr. Vahlen, R. Shen
XCOM: Enemy Crossfire by cxy31337 reviews
AU. What has three fronts, one overt, one covert and one within? A war against alien invasions. When 5 university students stumble upon a gun fight, and contaminated with alien nanites, they soon find themselves under the auspice of an agency tasked to defend the world from alien threats. With escalating conflict abound, their newfound powers are the only key to winning the war.
Crossover - Animorphs & X-Com - Rated: T - English - Adventure/Drama - Chapters: 2 - Words: 6,400 - Reviews: 1 - Favs: 4 - Follows: 7 - Updated: 6/6/2020 - Published: 4/14/2020 - Cassie, Jake, Marco, Rachel
It's Always Sunny In The Quarantine Zone by DamnedBeret reviews
Against the full might of the horny Manono forces, the alluring wills of aroused old gods, and cheap Lovecraftian shout-outs lay a jaded, battle-hardened, and stretched thin XCOM and the Resistance. Join a beleaguered fireteam and the hypocritical team leader as they try to survive the Northern Quarantine Zone with their balls, freedom and sanity intact.
Crossover - Monster Girl Encyclopedia & X-Com - Rated: M - English - Fantasy - Chapters: 3 - Words: 26,746 - Reviews: 17 - Favs: 39 - Follows: 65 - Updated: 5/29/2020 - Published: 5/6/2020 - Bradford, OC, Van Doorn, Druella
Unknown Contact by ecarden reviews
The obligatory Mass Effect-XCOM crossover, just set a little earlier than most. The Migrant Fleet is looking for new worlds, new tech, new allies. Humanity would very much like to not be exterminated by aliens from beyond the stars. SYNERGY!
Crossover - X-Com & Mass Effect - Rated: M - English - Adventure/Sci-Fi - Chapters: 18 - Words: 126,651 - Reviews: 143 - Favs: 448 - Follows: 608 - Updated: 4/23/2020 - Published: 6/15/2017 - U. Wrex, Tali'Zorah, Joker, Shepard
A dire mistake by possibly Gigan reviews
ADVENT has been gone for ten years. In that time, the commander had gotten married, had three kids, and got things as close to what they were before the invasion as possible. But what happens when a new foe appears and tries to destroy it all? Thus, XCOM fought.
Crossover - X-Com & Gate - Jietai Kare no Chi nite, Kaku Tatakeri - Rated: M - English - Chapters: 4 - Words: 6,908 - Reviews: 11 - Favs: 62 - Follows: 67 - Updated: 4/9/2020 - Published: 4/1/2019
XCOM: Free as Bird by MercBoss
A simple recon mission for XCOM operative Faith Connors
Crossover - X-Com & Mirror's Edge - Rated: T - English - Adventure/Sci-Fi - Chapters: 2 - Words: 927 - Follows: 2 - Updated: 4/9/2020 - Published: 2/24/2020 - Bradford, Firebrand, Faith C., Kate C.
Operation: Go Home by The Sauce Boss reviews
You tell someone from 2015 that aliens will rule the world by 2016, they'll call you a liar. You tell someone from 2020 that XCOM will rise up to fight said aliens, they'll call you a liar. You tell XCOM that a bunch of teenagers are gonna be their only hope of survival, they'll most likely shoot you after calling you a liar.
Crossover - X-Com & RWBY - Rated: M - English - Suspense/Supernatural - Chapters: 37 - Words: 212,076 - Reviews: 15 - Favs: 88 - Follows: 96 - Updated: 3/28/2020 - Published: 12/20/2018 - Jaune A., Pyrrha N., L. Ren, Nora V.
The Dominion rises by tombstone199998 reviews
The dominion has stood strong for centuries since the Ethereal war, under the guidance of the Emperor the Terrans have risen beyond the wildest of dreams, what happens when they encounter the a race of council exiles in desperate need.
Crossover - X-Com & Mass Effect - Rated: M - English - Sci-Fi - Chapters: 5 - Words: 25,421 - Reviews: 78 - Favs: 451 - Follows: 664 - Updated: 3/11/2020 - Published: 6/18/2017
XCOM: Remnant Unknown by DrAmishMD reviews
The sequel to XCOM: RWBY Within. Teams RWBY and JNPR return to Remnant in time for the Vytal Festival. They're relieved to finally have their lives get back to normal after nine months on war-torn Earth, but is the life of a huntsman ever truly normal?
Crossover - X-Com & RWBY - Rated: M - English - Adventure/Sci-Fi - Chapters: 48 - Words: 488,809 - Reviews: 1178 - Favs: 1,284 - Follows: 1,381 - Updated: 2/20/2020 - Published: 7/22/2016 - Team RWBY, Team JNPR - Complete
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