Halo and Mass Effect Crossovers
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The Halo Effect by Agentweapon Proelium-Tempus reviews
The UNSC dispatches a small task force to investigate an artefact with origins not of the Orion Arm. The Citadel Races, including the Systems Alliance, are in for an eye opener when two new players in galactic prowess are not only technologically superior but also not bound by the Element Zero and its constraints. Rated T for reasons. AU in both Halo and ME events.
Rated: T - English - Adventure/Humor - Chapters: 16 - Words: 50,729 - Reviews: 338 - Favs: 915 - Follows: 1,212 - Updated: 1h - Published: 8/6/2015 - Master Chief/John-117, OC, Shepard (F)
Against the Odds by Agentweapon Proelium-Tempus reviews
The Insurrection killed millions, but Humanity recovered. The Human-Flood War killed billions, but Humanity prevailed. Humanity again stands alone in the face of both persistent and threatening rivals. They are outnumbered and outgunned and are against tenacious opposition, but then again, Humanity has always had the ability for surviving the impossible. Heavy AU
Rated: T - English - Suspense/Humor - Chapters: 4 - Words: 17,170 - Reviews: 56 - Favs: 217 - Follows: 332 - Updated: 1h - Published: 8/20 - Master Chief/John-117, OC, Shepard (F), Illusive Man
Clash of Galaxies by The Great Lord Dovahkiin reviews
Multicrossover between Halo, Star Wars, Mass Effect, JC's Avatar, and RvB
Rated: T - English - Chapters: 8 - Words: 12,185 - Reviews: 24 - Favs: 42 - Follows: 48 - Updated: 9/22 - Published: 8/28
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: 6 - Words: 57,425 - Reviews: 80 - Favs: 109 - Follows: 128 - Updated: 9/18 - Published: 5/19
Mass Effect: Republic by T.rex98 reviews
After Mass Relay 314 is, suddenly, activated, the Citadel Council discovers that they're not the only massive power in the galaxy. However, will this alliance of races prove to be friend or foe? I don't own anything.
Rated: T - English - Sci-Fi - Chapters: 3 - Words: 10,092 - Reviews: 47 - Favs: 130 - Follows: 180 - Updated: 9/17 - Published: 9/5
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: 21 - Words: 188,940 - Reviews: 715 - Favs: 1,220 - Follows: 1,544 - Updated: 9/15 - Published: 3/27/2011 - Master Chief/John-117, Tali'Zorah, Miranda L., Shepard (M)
Mass Effect: The New Journey by Arashi the Solar Phoenix reviews
During a Joint Deployment, the UNSC Infinity and Her Sangheili allies are suddenly thrown into a new Galaxy, and end up near Charon before the Systems Alliance discovers the Charon Relay. Alliances are forged and how will the galaxy react to an aggressive humanity that not only doesn't use Mass Effect technology, but will not let anyone stand in their way of expansion? AU PreME1
Rated: T - English - Sci-Fi/Adventure - Chapters: 18 - Words: 179,291 - Reviews: 1182 - Favs: 1,810 - Follows: 2,235 - Updated: 9/14 - Published: 1/26/2014
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 is plunged in infighting and the Citadel Races are 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: 10 - Words: 103,082 - Reviews: 456 - Favs: 443 - Follows: 582 - Updated: 9/10 - Published: 3/13/2013
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: 12 - Words: 99,374 - Reviews: 335 - Favs: 627 - Follows: 829 - Updated: 9/9 - Published: 1/25/2015 - J. Cutter, P. Cole, U. Wrex, Aria T'Loak
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: 12 - Words: 81,754 - Reviews: 74 - Favs: 128 - Follows: 153 - Updated: 9/9 - Published: 5/3 - Master Chief/John-117, Cortana, Admiral Hackett, Shepard (M)
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: 30 - Words: 292,224 - Reviews: 2376 - Favs: 2,531 - Follows: 3,103 - Updated: 8/30 - Published: 10/9/2013 - Master Chief/John-117, T. Lasky, Admiral Hackett, Shepard (M)
HaloMass effect: To the Gates of Hell by EliteZealot936 reviews
What would happen if the Sangheili, Kig-Yar, and Sharqoi evolved in the ME universe? Well thats what this story is about. AU (Duh)
Rated: T - English - Adventure/Sci-Fi - Chapters: 3 - Words: 6,427 - Reviews: 8 - Favs: 24 - Follows: 22 - Updated: 8/29 - Published: 4/9
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: 20 - Words: 136,681 - Reviews: 521 - Favs: 835 - Follows: 1,145 - Updated: 8/26 - Published: 11/26/2013 - Master Chief/John-117, Cortana, Shepard (F)
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: 14 - Words: 29,980 - Reviews: 188 - Favs: 513 - Follows: 746 - Updated: 8/26 - Published: 1/6/2015 - Master Chief/John-117, T. Hood
Infinity by casquis reviews
Space is infinite, but under the right conditions even a galaxy can feel too small.
Rated: T - English - Sci-Fi - Chapters: 8 - Words: 51,961 - Reviews: 229 - Favs: 314 - Follows: 478 - Updated: 8/19 - Published: 10/12/2015
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: 7 - Words: 12,095 - Reviews: 11 - Favs: 33 - Follows: 62 - Updated: 8/13 - Published: 12/10/2015 - Gravemind, Shepard (F), Harbinger
Humanity at War: Earth's Last Stand by EliteOp reviews
A hero from another time wakes up in a whole new war. Except this time the commander is not the main protagonist.
Rated: T - English - Romance/Sci-Fi - Chapters: 10 - Words: 6,834 - Reviews: 11 - Favs: 23 - Follows: 21 - Updated: 8/12 - Published: 1/24/2015
ONI Dossier: Jameson Locke by Mediam Noctem reviews
A glimpse into the background of Lieutenant Commander Jameson Locke, ONI Field Agent - with technical details, history, tactics, and more! Related to the upcoming story: "Dusk Before Dawn".
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 3,107 - Reviews: 3 - Favs: 3 - Follows: 2 - Published: 7/31
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: 189 - Favs: 122 - Follows: 110 - Updated: 7/23 - Published: 6/21/2013 - Master Chief/John-117, Shepard (M)
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: 42 - Follows: 58 - 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: 52 - Follows: 68 - Updated: 7/17 - Published: 12/26/2014 - Cortana, SPARTAN-B312/Noble Six, Shepard (M)
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: 24,679 - Reviews: 62 - Favs: 39 - Follows: 49 - Updated: 7/16 - Published: 1/15/2015 - Gravemind
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: 7,425 - Reviews: 9 - Favs: 22 - Follows: 30 - Updated: 7/10 - Published: 4/1
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: 69 - Favs: 217 - Follows: 268 - Updated: 7/1 - Published: 7/15/2015 - Master Chief/John-117, Shepard (F)
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: 286 - Favs: 798 - Follows: 1,000 - Updated: 6/21 - Published: 3/2/2015 - T. Hood, Cortana, Shepard (F)
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