Halo and Mass Effect Crossovers
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Heroes UNITE! by So-Pro Warrior reviews
Commander Shepard and his team have gathered together the races of their Galaxy in an effort to defeat the Reapers. But is it enough? When the Commander and his team come across a strange woman they find out that if they are to truly defeat the Reapers once and for all. They will need all the help they can get. But not from their Universe. Multiverse Crossover!
Rated: T - English - Adventure/Sci-Fi - Chapters: 21 - Words: 488,244 - Reviews: 174 - Favs: 116 - Follows: 105 - Updated: 7h - Published: 6/21/2013 - Master Chief/John-117, Shepard (M)
The Spartan Effect by Gatekeeper333 reviews
Everyone's favorite Spartan is looking for a new purpose, lucky for him, the Commander his happy to oblige.
Rated: T - English - Chapters: 18 - Words: 168,844 - Reviews: 640 - Favs: 1,115 - Follows: 1,432 - Updated: 7/22 - Published: 3/27/2011 - Master Chief/John-117, Tali'Zorah, Miranda L., Shepard (M)
Mirrored Fates by long night of solace reviews
After the defeat of the didact, the galactic hero of the halo universe - Masterchief and his loyal blue team members embark on a strange new journey to an unknown universe in which later they come into contact with that universe's hero - Commander Shepard. Facing an unknown enemy, fighting a new war, its up to the heroes to save the day together.
Rated: T - English - Sci-Fi/Adventure - Chapters: 11 - Words: 75,293 - Reviews: 57 - Favs: 108 - Follows: 125 - Updated: 7/22 - Published: 5/3 - Master Chief/John-117, Cortana, Admiral Hackett, Shepard (M)
The Reclamation has already begun by Fade Maybe reviews
The Requiem Event has ended. The Reaper War is reaching its climax. In 2557 Military Calendar and 2186 Common Era, the UNSC finds itself on the brink of infighting and the Citadel Races on the brink of annihilation. Light will be shed upon questions the Forerunners left behind. Ancient threats rise again. This is only the next step in the Reclamation, and it is too late to stop it.
Rated: T - English - Adventure/Sci-Fi - Chapters: 9 - Words: 88,870 - Reviews: 441 - Favs: 407 - Follows: 541 - Updated: 7/20 - Published: 3/13/2013
The Cycle by Church -Caboose- Shepard reviews
Fighting off extinction Shepard must find the legacy left to humanity by the Forerunners. And find a way to defeat both the Reapers and the Prophet of Truth from gaining the power to destroy all sentient life in the Galaxy.
Rated: T - English - Sci-Fi/Adventure - Chapters: 33 - Words: 92,054 - Reviews: 120 - Favs: 40 - Follows: 56 - Updated: 7/19 - Published: 8/29/2012 - Arbiter, Prophet of Truth, Shepard (M), OC
The Age of Extinction (A New Battleground Part 2) by AlphaGuardian reviews
The Collectors have been defeated, but now the galaxy faces extinction from the Reapers. Their last hope lies in the brave men and women of the SSV Normandy and their Spartan ally. But even they will not be able to save everyone, and everyone has their breaking point. But the fate of the galaxy rests on their shoulders, and failure means extinction.
Rated: T - English - Sci-Fi/Adventure - Chapters: 9 - Words: 26,037 - Reviews: 14 - Favs: 49 - Follows: 65 - Updated: 7/17 - Published: 12/26/2014 - Cortana, SPARTAN-B312/Noble Six, Shepard (M)
Effects of a Titan by greeneman42 reviews
A small salvage ship comes across an interesting find while searching. Set before Halo 4 and before ME 2
Rated: T - English - Adventure/Sci-Fi - Chapters: 19 - Words: 127,332 - Reviews: 489 - Favs: 770 - Follows: 1,062 - Updated: 7/16 - Published: 11/26/2013 - Master Chief/John-117, Cortana, Shepard (F)
Accounts of the Flood conflicts by hunter 139 reviews
A series of one-shots depicting several franchises and their encounters with the Flood. I do not own Halo or any other franchises depicted in these stories.
Rated: T - English - Horror/Sci-Fi - Chapters: 14 - Words: 24,660 - Reviews: 61 - Favs: 35 - Follows: 43 - Updated: 7/16 - Published: 1/15/2015 - Gravemind
Red Cobra by Billybobjoe47s reviews
Last time the UNSC discovered a mysterious alien artifact, the Halos came within seconds of activating. Every problem the UNSC has had in the last 50 years has been because of aliens and their blasted artifacts. So when a newly-surveyed system holds a mysterious artifact, there is great cause for worry. Operation RED COBRA is intended to remedy that worry- by any means necessary.
Rated: T - English - Sci-Fi/Adventure - Chapters: 13 - Words: 27,546 - Reviews: 176 - Favs: 491 - Follows: 704 - Updated: 7/13 - Published: 1/6/2015 - Master Chief/John-117, T. Hood
Dusk Before Dawn archives: UNSC and Citadel by Mediam Noctem reviews
A glimpse into the inner workings of tomorrow's superpowers, a codex to explain the darker universe at large. Related to the upcoming story: "Dusk before Dawn".
Rated: T - English - Sci-Fi - Chapters: 3 - Words: 7,391 - Reviews: 9 - Favs: 20 - Follows: 28 - Updated: 7/10 - Published: 4/1
The Infinity Effect by creamofwheat2311 reviews
After discovering a Precursor artifact, the UNSC Infinity and the Sangheili Shadow of Intent are transported to a universe unlike anything they have ever seen, and forced into a war against a foe they never could have imagined: the Reapers. Alliances are founded, friendships are formed, and decisions are made that will change this galaxy forever. Post Halo 4, Pre ME3. AU
Rated: T - English - Sci-Fi/Adventure - Chapters: 29 - Words: 283,218 - Reviews: 2319 - Favs: 2,454 - Follows: 3,023 - Updated: 7/2 - Published: 10/9/2013 - Master Chief/John-117, T. Lasky, Admiral Hackett, Shepard (M)
Shadow Contingency by Andrithir reviews
As the war against the Covenant takes another turn, humanity must confront a wider galactic community beyond the known regions.
Rated: T - English - Adventure/Sci-Fi - Chapters: 5 - Words: 55,400 - Reviews: 65 - Favs: 203 - Follows: 253 - Updated: 7/1 - Published: 7/15/2015 - Master Chief/John-117, Shepard (F)
Heroes of Fire by Kamzil118 reviews
The Reapers arrive and the galaxy is under threat, but when Shepard and her friends are pit against the odds. Many will die, worlds will perish, and the Heroes of the Stars shall return.
Rated: T - English - Adventure - Chapters: 2 - Words: 2,749 - Reviews: 24 - Favs: 20 - Follows: 18 - Updated: 6/30 - Published: 6/10
The Sum is Greater than its Parts by Maersikai reviews
Having long since combined forces, a fleet of the Humans and Covenants finest are torn from the universe they know to be thrown in to a strange and desolate reality. They will strive to uphold the Mantle against the Mass Effect's most Ancient Enemy. Will they break the cycle?
Rated: T - English - Sci-Fi - Chapters: 18 - Words: 168,017 - Reviews: 279 - Favs: 786 - Follows: 982 - Updated: 6/21 - Published: 3/2/2015 - T. Hood, Cortana, Shepard (F)
Halo Fire phoenix: Cold war by Jochern reviews
It has been one month sense the First Contact War ended. Both the UNSC and the Citadel enter a state of cold war. (AU story)
Rated: T - English - Friendship/Sci-Fi - Chapters: 4 - Words: 15,261 - Reviews: 18 - Favs: 26 - Follows: 36 - Updated: 6/21 - Published: 6/19 - Garrus V., U. Wrex, Tali'Zorah, U. Grunt
Legendary Contact by Kamzil118 reviews
After a life-threatening conflict of extinction, humanity finds itself an anomaly to be found by their own anomaly. However, the strange new technology ends up meeting with an alien society which surprises both parties as a dark future lays ahead of the UNSC and an old Finnish Badass.
Rated: T - English - Sci-Fi - Chapters: 6 - Words: 10,789 - Reviews: 30 - Favs: 64 - Follows: 97 - Updated: 6/8 - Published: 3/19 - Complete
Book One: Dawn of a New Age by DragonheartODST reviews
Humanity had been expanding across the stars for over 5 centuries in relative peace. But an alien alliance known as the Covenant wishes to destroy humanity entirely. Now threatened with extinction, can the fate of just one battle-scared survivor change the events of the war and those participating in it? Multi-crossover with Halo, Mass Effect, and a little bit of StarCraft.
Rated: T - English - Adventure - Chapters: 4 - Words: 35,180 - Reviews: 38 - Favs: 74 - Follows: 87 - Updated: 6/5 - Published: 5/19
Exodus of the Damned by Codename-SURGEON reviews
The Reapers fell and with them fell our worlds. We drift alone in search of home and hope to one day build again. An artifact found provides a ray of hope. And those few who ventures through will seal our doom or not. Other worlds and other chances gives the Damned needed hope.
Rated: T - English - Sci-Fi/Adventure - Chapters: 10 - Words: 56,597 - Reviews: 88 - Favs: 193 - Follows: 311 - Updated: 6/1 - Published: 1/17 - T. Lasky, Garrus V., Admiral Hackett
Shadow of N7 by jmichaelm99 reviews
During the events of Mass Effect 2, Commander Shepard discovers a SPARTAN super soldier stranded in the far reaches of the galaxy. Befriending this new ally, she embarks on her mission to shut down the collectors. During her mission she uncovers a dark truth about the reapers and the galaxies of the universe.
Rated: T - English - Sci-Fi - Chapters: 4 - Words: 9,640 - Reviews: 9 - Favs: 22 - Follows: 47 - Updated: 5/30 - Published: 12/10/2015 - Gravemind, Shepard (F), Harbinger
Universal Restriction by Chaoswind2 reviews
First part of a three part project: The Great war was finally over, with the Covenant and the Flood defeated there were no enemies left to fight, mankind could finally take a breath and enjoy the peace they had earned after twenty seven years of a war that had claimed twenty three billion lives. Or so they hoped. But the galaxy has never been that kind.
Rated: T - English - Sci-Fi/Adventure - Chapters: 5 - Words: 39,222 - Reviews: 62 - Favs: 161 - Follows: 209 - Updated: 5/26 - Published: 6/20/2013 - Master Chief/John-117, Cortana
A Feeling of Importance by LebendenToten reviews
Well, after reading quite a bit of fanfiction I decided that maybe it was finally time for me to try and crank out one of my own. This is going to be a self insert story of sorts that starts in the Halo universe then eventually transitions to Mass Effect. This is my first Fanfic so be nice :P and constructive criticism/suggestions welcome! Rated T mainly for language.(changed to T)
Rated: T - English - Adventure/Friendship - Chapters: 22 - Words: 38,586 - Reviews: 167 - Favs: 206 - Follows: 269 - Updated: 5/24 - Published: 11/6/2014 - Master Chief/John-117, C. Halsey, OC, Shepard (F)
Mass Effect: Clash of Civilizations by Eterna1Soldier reviews
In 2157 a Citadel Council exploratory vessel is tasked with opening a dormant Relay into unknown regions of the galaxy. What they find is something they never expected. What happens when two civilizations centered around different technologies clash?
Rated: T - English - Adventure/Mystery - Chapters: 21 - Words: 96,812 - Reviews: 3157 - Favs: 3,913 - Follows: 4,599 - Updated: 5/22 - Published: 10/13/2011 - Tali'Zorah
The Sangheili Effect by Allard-Liao reviews
Years after the Covenant Remnant founded by Jul M'dama had been destroyed, a new Covenant of Prophet-led Brutes attempt to attack humanity and its allies. One of the task forces sent to squash the upstarts triggers an unprecedented Slip-Space event. This is my very, VERY long-overdue answer to the Crossover Challenge by B1ue Ange1s. Rated T for now.
Rated: T - English - Sci-Fi/Adventure - Chapters: 1 - Words: 2,288 - Reviews: 6 - Favs: 11 - Follows: 22 - Published: 5/20 - Tali'Zorah, Shepard (M)
First Contact by Shadythief reviews
When the SSV Normandy becomes lost in space, they chance upon an undiscovered system. They find an unknown race, who use strange technology previously thought impossible. Could these aliens be the key to a far off future war? Or will they only cause more destruction?
Rated: K+ - English - Sci-Fi/Adventure - Chapters: 6 - Words: 26,424 - Reviews: 65 - Favs: 143 - Follows: 205 - Updated: 5/20 - Published: 3/18 - Arbiter, Shepard (F), Garrus V.
Halo-Mass Effect: Altered-Destiny by Azores reviews
In 2531 during the early years of the Great War, UNSC Spirit of Fire went missing and was declared lost with all hands. But what if the Spirit wasn't lost and adrift in space. What if it was sent to another Galaxy, before the Humans of this Galaxy hadn't discovered a certain set of ruins yet. How will Humanity's future change? How will the Galaxy be changed? Start 2100 AD. Book 1
Rated: T - English - Sci-Fi - Chapters: 10 - Words: 93,384 - Reviews: 302 - Favs: 603 - Follows: 802 - Updated: 5/17 - Published: 1/25/2015 - J. Cutter, P. Cole, U. Wrex, Aria T'Loak
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