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Psi-Effect (The Bad End Series) by JohnAnonymous reviews
A fanfic based on Cap'n Chrysalid's Psi-Effect story but in the Bad End timeline. This fic consists of diary entries by Liara T'soni, each one a thousand words long. Enjoy
Crossover - X-Com & Mass Effect - Rated: K - English - Horror - Chapters: 2 - Words: 2,277 - Reviews: 4 - Favs: 8 - Follows: 18 - Updated: 5/21 - Published: 5/9
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: 12 - Words: 16,807 - Reviews: 6 - Favs: 14 - Follows: 21 - Updated: 5/15 - Published: 11/6/2020 - OC, Adam Jensen
XCOM: Enemy Expanded by DarthHollow reviews
We defeated the Elders. We took their technology and made it our own to advance into the stars. After so long we surprisingly made allies while unsurprisingly made enemies. Now we find our place and stand firm in this galaxy. Pray to those that believe us weak. For we will not.
Crossover - X-Com & Mass Effect - Rated: M - English - Sci-Fi - Chapters: 7 - Words: 33,269 - Reviews: 42 - Favs: 158 - Follows: 254 - Updated: 5/15 - Published: 8/6/2020
XCOM: Stargate Initiative by ShirouKuroEmiya reviews
XCOM Project succeeded and failed. When the Ethereals decided to fight seriously, they came back with much more powerful weapons and greater numbers than ever before. Nations around the world fell one by one and ADVENT sprang up in their place. XCOM lost, but it still had its Commander and people. Decades later, hope for victory laid beyond the world, the Stargate.
Crossover - Stargate: SG-1 & X-Com - Rated: T - English - Adventure/Drama - Chapters: 1 - Words: 3,178 - Reviews: 6 - Favs: 19 - Follows: 26 - Published: 5/12
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: 14 - Words: 62,560 - Favs: 3 - Follows: 1 - Updated: 5/10 - Published: 3/10
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: 16 - Words: 85,989 - Reviews: 59 - Favs: 84 - Follows: 106 - Updated: 5/10 - Published: 12/9/2019 - Bradford, Ruby R.
The Bureau: Summer Declassified by Joey245 reviews
Following her final confrontation with Salem, Summer Rose is mysteriously transported to another world on the brink of war - not only with itself, but with an alien invasion. Can she navigate this strange new world? Will she ever find a way back home to Remnant? And what secrets does the Bureau hold? (Inspired by DrAmishMD's excellent XCOM/RWBY stories.)
Crossover - X-Com & RWBY - Rated: M - English - Adventure - Chapters: 23 - Words: 232,831 - Reviews: 87 - Favs: 100 - Follows: 135 - Updated: 4/25 - Published: 7/22/2019 - R. Shen, OC, Summer R.
XCOM: Mythos Point by Zeroraid reviews
The Ethereal War ended a long time ago, and Humanity took topreparing for the Ethereal's return. Unfortunately as they prepared for one enemy, a second crept out the shadows of the ocean and the cities they defended. It is the years 2177, and the New Earth Government keeps a tight grasp on world after the open warfare between XCOM, sea monster and cultist have taken to the shadows.
Crossover - X-Com & Cthulhu Mythos - Rated: T - English - Sci-Fi/Supernatural - Chapters: 4 - Words: 14,547 - Reviews: 4 - Favs: 3 - Follows: 4 - Updated: 4/23 - Published: 12/24/2020 - OC - Complete
XCOM: War of the Maidens by DrAmishMD reviews
With the secret of Remnant's past in her hands, Ruby Rose must work with her teammates and their allies to bring an end to her world's greatest threat.
Crossover - X-Com & RWBY - Rated: M - English - Adventure/Sci-Fi - Chapters: 2 - Words: 19,674 - Reviews: 39 - Favs: 135 - Follows: 161 - Updated: 4/23 - Published: 3/21 - Team RWBY, Team JNPR
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: 62 - Favs: 130 - Follows: 141 - Updated: 4/16 - 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: 18 - Favs: 66 - Follows: 103 - Updated: 4/14 - Published: 3/25
Tales From The Avenger by DrAmishMD reviews
A collection of one-shots written by readers of XCOM: RWBY Within and XCOM: Remnant Unknown.
Crossover - X-Com & RWBY - Rated: M - English - Humor/Adventure - Chapters: 45 - Words: 170,185 - Reviews: 99 - Favs: 134 - Follows: 163 - Updated: 3/31 - Published: 7/3/2018
GATE - Thus XCOM Fought There! by ShirouKuroEmiya reviews
Itami Yoji, a former XCOM Operative and currently living as Otaku, had been out in Ginza looking to attend an anime convention. The very last thing was him expecting fighting a unknown enemy from another world. Not only that, but he found himself leading an XCOM team known as Third Recon across the Gate. How will Falmart respond to the might and influence of XCOM?
Crossover - X-Com & Gate - Jietai Kare no Chi nite, Kaku Tatakeri - Rated: T - English - Adventure/Drama - Chapters: 1 - Words: 4,736 - Reviews: 13 - Favs: 48 - Follows: 63 - Published: 3/29 - Itami
BRWL: Ally Unknown 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: 6 - Words: 39,222 - Reviews: 11 - Favs: 15 - Follows: 27 - Updated: 3/6 - Published: 11/8/2020 - EXALT, Blake B., Penny P., Team RWBY
Harry Potter and the Extraterrestrial Combat Unit by defiasstone2 reviews
Harry Potter, sick of the Wizarding world and mourning the loss of his closest companions, enacts a ritual not completed since the time of Merlin. His aim is to get away from the pain and bitter memories of his old life, and with the appearance of aliens and flurries of green plasma death, in this new world he will not be short of distractions... Based on X-Com: Enemy Unknown
Crossover - Harry Potter & X-Com - Rated: M - English - Chapters: 11 - Words: 48,854 - Reviews: 159 - Favs: 641 - Follows: 890 - Updated: 3/4 - Published: 1/6/2016
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: 12 - Words: 68,891 - Reviews: 253 - Favs: 1,399 - Follows: 1,737 - Updated: 2/22 - Published: 9/19/2017 - [Skitter, Panacea] [Danny H., Miss Militia]
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: 5 - Favs: 27 - Follows: 55 - Updated: 2/2 - Published: 1/15 - 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: 11 - Follows: 12 - Updated: 1/15 - Published: 8/12/2018 - Bradford, Princess Celestia, Sunset Shimmer, OC - Complete
Turned Tables by ShadowofHawk55 reviews
Once the invaded, now the invaders. How will the people of Psi Terra handle the conflict between Earth and Pandora? Edit Title changed from Revelations
Crossover - X-Com & Avatar - Rated: M - English - Sci-Fi/Drama - Chapters: 8 - Words: 31,345 - Reviews: 13 - Favs: 9 - Follows: 11 - Updated: 1/6 - Published: 5/25/2020
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: 365 - Follows: 470 - 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: 28 - Favs: 125 - Follows: 177 - 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: 4 - Follows: 4 - Updated: 12/1/2020 - Published: 9/8/2020
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: 7 - Words: 47,183 - Reviews: 31 - Favs: 96 - Follows: 126 - Updated: 11/30/2020 - Published: 12/31/2019
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: 5 - Favs: 21 - Follows: 28 - 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
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