X-Com and Mass Effect Crossovers
I Am Watchful I Am Necessary by TheConstellation reviews
Decades have past since the Ethereals threat was defeated and humanity has emerged united and stronger than ever for the conflict it faced. Now after discovering the Prothean Archives on Mars, humanity is about to end up on a much larger stage than it ever expected to play on when yet another alien threat comes knocking. And again, X-COM stands ready to fight. Vigilo Confido.
Rated: T - English - Sci-Fi - Chapters: 9 - Words: 18,569 - Reviews: 337 - Favs: 633 - Follows: 870 - Updated: 2/25 - Published: 9/30/2013 - Admiral Hackett
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 fusion.
Rated: T - English - Sci-Fi/Adventure - Chapters: 12 - Words: 112,376 - Reviews: 299 - Favs: 547 - Follows: 616 - Updated: 2/18 - Published: 9/2/2014
Aleandrea's Alien Primer - Combined and Condensed Edition by 5 Coloured Walker reviews
Alien's aren't just people with rubber faces and funny hats.
Rated: T - English - Sci-Fi - Chapters: 2 - Words: 2,189 - Reviews: 2 - Favs: 1 - Follows: 1 - Published: 2/18
Council's notes on Humanity by 5 Coloured Walker reviews
This is the Citadel Codex as it applies to Humans in the [TBD] world, who's current stories include: Busy Stars This however is not the codex of general things however, not is it human's documentation on aliens.
Rated: T - English - Sci-Fi - Chapters: 2 - Words: 2,321 - Reviews: 1 - Favs: 11 - Follows: 15 - Published: 2/11
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...
Rated: T - English - Humor/Sci-Fi - Chapters: 12 - Words: 118,023 - Reviews: 338 - Favs: 1,149 - Follows: 1,418 - Updated: 1/29 - Published: 7/19/2014 - U. Wrex, Daro'Xen, Shepard (F), Shepard (M)
Smoke on the Water by P.H. Wise reviews
Centuries after the Ethereal war, after humanity discovered a galaxy filled with alien life, after the defeat of Sovereign, the abductions have begun again. This time, entire human colonies are disappearing. And a reborn Commander Shepard and the long-thought defunct Extraterrestrial Combat Unit may be the only thing standing between humanity and extinction... (XCOM/Mass Effect)
Rated: T - English - Sci-Fi - Chapters: 6 - Words: 45,280 - Reviews: 32 - Favs: 109 - Follows: 164 - Updated: 1/20 - Published: 7/19/2014 - Shepard (F), Liara T'Soni, Miranda L.
All terrans by SleeperS reviews
First try. OP-Humanity. Dimensional travel. MY playground. Not sure what it will be... Better description i will add with more chapters.
Rated: T - English - Chapters: 2 - Words: 2,302 - Reviews: 7 - Favs: 8 - Follows: 13 - Updated: 10/24/2014 - Published: 10/23/2014
Cause and Effect by Eotyrannus reviews
The Temple Ship threatened to eradicate either XCOM's finest or the entire human race. Instead, it took itself into a whole new universe, where the races of the galaxy used the incredible Element Zero to cross the stars. No one has any idea what's coming... *Being replaced with a remake*
Rated: T - English - Sci-Fi - Chapters: 7 - Words: 21,235 - Reviews: 62 - Favs: 211 - Follows: 295 - Updated: 9/15/2014 - Published: 5/18/2014
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.
Rated: T - English - Sci-Fi - Chapters: 4 - Words: 94,510 - Reviews: 152 - Favs: 497 - Follows: 699 - Updated: 8/31/2014 - Published: 3/20/2014
X-COM: Enduring Legacy by Wixeron reviews
Humanity has survived, adapted and won against extraterrestrial threats even before they leave Earth. Now, with a changed mentality, they took to the stars and would bring about a revolution to the galactic community and inadvertently, change the course of the Cycle.
Rated: T - English - Sci-Fi - Chapters: 4 - Words: 21,696 - Reviews: 38 - Favs: 137 - Follows: 189 - Updated: 8/23/2014 - Published: 7/27/2014
X-Com: Enemy Without by Cobra of England reviews
The Ethereal War left Humanity scarred. The aftershocks left them bruised. But they rose up once again, and once again, Humanity must fight against the alien threat without.
Rated: T - English - Sci-Fi - Chapters: 5 - Words: 9,290 - Reviews: 47 - Favs: 95 - Follows: 156 - Updated: 7/30/2014 - Published: 5/28/2014
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? Only time will tell, as XCOM and the Council meet in a galaxy soon to be shattered.
Rated: T - English - Sci-Fi/Adventure - Chapters: 14 - Words: 51,172 - Reviews: 281 - Favs: 537 - Follows: 716 - Updated: 7/7/2014 - Published: 5/11/2014 - OC
The Galaxies Black Ops by Excalibursoul reviews
The XCOM project continues on while Shepard saves the galaxy XCOM will operate without the public knowing about them I know not the best work but I'll flesh it out.
Rated: T - English - Chapters: 4 - Words: 3,969 - Reviews: 4 - Favs: 12 - Follows: 13 - Updated: 7/6/2014 - Published: 5/4/2014
When Civilizations Meet: Tali's School Days by Generatedname reviews
A less serious side story to my fic 'When Civilizations Meet', this fic details Tali and her fellow Psionic Quarian students' adventures in a Terran Alliance elementary school. This fic has little to no effect on the storyline of When Civilization Meet. WARNING: Contains My Little Chryssalid.
Rated: T - English - Humor/Sci-Fi - Chapters: 4 - Words: 5,806 - Reviews: 28 - Favs: 79 - Follows: 101 - Updated: 6/6/2014 - Published: 5/18/2014 - Garrus V., Tali'Zorah, Kal'Reegar, Solana Vakarian
The XCOM Effect by Havocfrost reviews
2183: Humanity has survived second contact, but now Eden Prime burns and the ancient boogeymen of Earth's past are set to destroy the fragile place Humanity has earned. Beset on all sides by indifferent allies and hostile alien races, only one man can bring the galaxy back from the brink and unite the disparate species against the real foe threatening them all.
Rated: T - English - Adventure/Sci-Fi - Chapters: 5 - Words: 47,921 - Reviews: 53 - Favs: 103 - Follows: 146 - Updated: 5/25/2014 - Published: 3/26/2014 - Saren A., Shepard (M)
Extradimensional Assistance by President John Henry Eden reviews
Commander Shepard found himself in command of six alien hunters from a neighboring parallel universe. Now, he has the new responsibility of trying to keep the XCOM operatives in his squad from tearing the Normandy crew apart with either rampant xenophobia, or just by plain old poor communication skills. Starts from ME2's Freedom's Progress. Ends in Collector Base? Not necessarily.
Rated: T - English - Sci-Fi/Friendship - Chapters: 4 - Words: 47,038 - Reviews: 41 - Favs: 93 - Follows: 119 - Updated: 3/11/2014 - Published: 2/23/2014 - Garrus V., Tali'Zorah, Shepard (M)
XCOM Mass Effect Crossover challenge by superezra reviews
i'm sary the original challenge got taken down because of some personal info if you read this is me then you now wot i'm talking about anyway package sacrifices him self to save the temple ship and to give the aliens back their freedom new earth government xcom renamed aliens (organic and sinthatic) gain equal wrights advans throw the threw the stars warp drives super careers bla
Rated: T - English - Adventure/Sci-Fi - Chapters: 3 - Words: 830 - Reviews: 11 - Favs: 2 - Follows: 2 - Updated: 1/25/2014 - Published: 10/10/2013
X-Com, a new threat by Deathtroll reviews
set in the X-Com universe, at 2100 hours GMT, a scientific expedition went dark, at 0100 Hours our colony on Shanxi went dark, sending an hostile aliens SOS, this is what happened after, please note I have not played ME1.
Rated: T - English - Sci-Fi - Chapters: 2 - Words: 1,329 - Reviews: 3 - Favs: 25 - Follows: 30 - Published: 11/22/2013 - Shepard (F)
XCOM: Second Contact by Agayek reviews
With the destruction of the Temple Ship humanity knew peace. XCOM never forgot their motto however, 'always vigilant, always reliable'
Rated: T - English - Sci-Fi/Adventure - Chapters: 26 - Words: 294,105 - Reviews: 976 - Favs: 1,688 - Follows: 1,764 - Updated: 9/15/2013 - Published: 1/1/2013
Across Time and Space, There's Always Earth by Wanderer D reviews
A new energy signal discovered in the middle of the Reaper invasion might be just what Shepard needs... or perhaps it might doom them all. Despite ending up in unexpected places, Shepard knows what she aims to protect, because, even across Time and Space... there's always Earth.
Rated: T - English - Adventure/Sci-Fi - Chapters: 1 - Words: 4,039 - Reviews: 17 - Favs: 48 - Follows: 89 - Published: 6/13/2013 - Shepard (F), Garrus V., Liara T'Soni, U. Wrex
The Volunteer by Primordial Soul reviews
A hero's duty never ends. A hero's journey never ceases. A hero never dies. If energy cannot be destroyed, then heroes never fall. They only move on. The Volunteer follows this creed. And in this new universe, the Volunteer will do what she does best. For she is XCOM. Always vigilant. Always reliable. Post ME1. Volunteer/Liara. ON-HOLD
Rated: T - English - Chapters: 1 - Words: 3,947 - Reviews: 23 - Favs: 50 - Follows: 86 - Published: 3/30/2013 - Liara T'Soni, Nyreen K.
The war that never ends by Masterblader158 reviews
Mankind survived against all odds and now they must do it again but this time much much harder and bigger. (Will fit in Marauder Shields at an appropriate time in the story) need reviews to help me improve and for suggestions.(On Hiatus)
Rated: T - English - Sci-Fi/Adventure - Chapters: 2 - Words: 1,615 - Reviews: 2 - Favs: 17 - Follows: 23 - Updated: 2/1/2013 - Published: 1/25/2013 - Marauder Shields
Xcom: Enemy Unknown: Shepard meets the Catalyst by Hoplite39 reviews
After defeating the alien leader in the temple ship, Xcom operative Colonel 'Spectre' Shepard meets a foe she had never met before called the Catalyst...Includes spoiler references for both ME3 and Xcom EU.
Rated: T - English - Humor/Parody - Chapters: 1 - Words: 812 - Reviews: 5 - Favs: 2 - Published: 1/26/2013 - Shepard (F), Catalyst - Complete
The New One's Destiny (Going through revision) by SniperInTheHouse reviews
Sacrificing his life to save earth he is sent to a new universe. Full of Xenos hate boils in his blood. Will Merc continue his Xenophobic and rip the Normandy crew apart or become a savior to humanity. Discontinued due to a better story done so now theres finally a small group of cross overs with xcom
Rated: T - English - Adventure/Mystery - Chapters: 8 - Words: 10,390 - Reviews: 16 - Favs: 10 - Follows: 14 - Updated: 12/10/2012 - Published: 11/7/2012 - Shepard (M)