Halo and Mass Effect Crossovers
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All the Stars by BlueWay reviews
When the Long Night of Solace is evaporated over Reach via the weaponized usage of a Slipspace Drive, it ferries with it in its swallowed sections the Covenant Empire and, more horrifyingly, the desperate measures that the UNSC used to fight them. When they are found in a universe on the precipice of their own history, the meaning of the term "Mass Effect" will change forever.
Rated: T - English - Sci-Fi/Adventure - Chapters: 44 - Words: 761,003 - Reviews: 1246 - Favs: 1,718 - Follows: 2,064 - Updated: 3/29 - Published: 6/8/2018 - SPARTAN-B312/Noble Six, Rookie
The Sins of our Fathers by MarkerMagnum reviews
Unknown to the Citadel Council, the Human-Covenant war nears its vicious end. Miranda Keyes is seconds too slow. Delta Halo fires, leaving UNSC space as a lifeless snapshot in time. The Citadel must morn the loss of a civilization they never knew.
Rated: T - English - Drama/Sci-Fi - Chapters: 5 - Words: 40,012 - Reviews: 171 - Favs: 457 - Follows: 661 - Updated: 3/28 - Published: 2/11 - Cortana, Councilor Valern, Councilor Tevos, Councilor Sparatus
Accounts of the Flood conflicts by hunter 139 reviews
A multicrossover 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: 41 - Words: 103,318 - Reviews: 212 - Favs: 178 - Follows: 195 - Updated: 3/17 - Published: 1/15/2015 - Gravemind - Complete
Drop into Hell by Lighting wolf knight reviews
They have a lot more to do before its done. Rated T for violence, death, and profanity.
Rated: T - English - Adventure/Romance - Chapters: 3 - Words: 11,962 - Reviews: 1 - Favs: 18 - Follows: 25 - Updated: 3/8 - Published: 2/3 - Miranda K., OC, Admiral Hackett, Shepard
The Reclamation by Fade Maybe reviews
Through ONI's manipulation, the UNSC stumbles upon a Mass Relay and is dragged into a new war. They'll discover the battered races of the Citadel, the political intrigue of its factions, and a second group of humans governed by the Systems Alliance, divided by Cerberus, and lead by Commander Shepard. Yet no one can stop what is to come: the Reclamation, and the death of the galaxy.
Rated: T - English - Drama/Suspense - Chapters: 55 - Words: 409,476 - Reviews: 1673 - Favs: 1,787 - Follows: 2,213 - Updated: 2/27 - Published: 3/13/2013
Operation Terra Sunrise HALO ( AU) x ME ( AU) by SimplyLaggy reviews
The Endless Swarm, known as the Reapers. Mostly defeated by the forerunners, yet after the death of almost all forerunners, they return. Now, the Reclaimers face them. Join Rebecca Shepard, a OMI Long-term undercover operative, as she goes undercover as Jane Shepard on Terra, Systems Alliance Earth, which was made by Ancient Humanity, as a ancient human remnant AI watches.
Rated: T - English - Chapters: 2 - Words: 4,521 - Reviews: 7 - Favs: 45 - Follows: 73 - Updated: 2/16 - Published: 2/9 - Illusive Man, Shepard
The USSC: A Timeline by SimplyLaggy reviews
A timeline of my USSC fanfic base. Feel free to use what's inside, but please gib me credit : REVAMP OUT 28/2/23 ENJOY
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 1,628 - Reviews: 2 - Favs: 10 - Follows: 10 - Published: 2/8
HALO x ME: The Relay by SimplyLaggy reviews
{ DELETING, DISCONTINUED }The Intergalactic Relay. It exists, to change everything, by a bored observer.
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 4,456 - Reviews: 6 - Favs: 28 - Follows: 37 - Published: 2/6
Un grand angle d'ombre by blackshamrock333 reviews
2560. L'humanité a survécu à la grande guerre contre les covenants et découvert l'espace concilien. Le Longest Day, prowler de l'UNSC en mission secrète, débarque en pleine attaque d'une colonie frontalière. Quelques jours plus tard, un médecin humain est découvert assassiné sur la Citadelle. Deux événements aléatoires, annonciateurs d'une course pour sauver la galaxie.
Rated: T - French - Sci-Fi/Adventure - Chapters: 2 - Words: 26,032 - Reviews: 2 - Favs: 6 - Follows: 8 - Updated: 2/6 - Published: 1/27
Immortal Galaxies by Lighting wolf knight reviews
An escape from an overrun galaxy lands them in another galaxy? What does being the biggest fish in the water gain you in a world without heavy hitters? Rated T for violence, death, and profanity.
Rated: T - English - Romance/Adventure - Chapters: 3 - Words: 4,777 - Reviews: 10 - Favs: 95 - Follows: 157 - Updated: 1/13 - Published: 11/11/2021 - [OC, Vetra N.] T. Hood
United Earths Empire: The Beginning of a New Age by Destarien reviews
What if three Universes once separate come together. three different humanities with three different paths of technology merge into one galaxy. Citadel space will never be the same because the Schahl Empire and UNSC are here. Two Civilizations, one at war and one ready for war.
Rated: T - English - Fantasy/Sci-Fi - Chapters: 8 - Words: 21,362 - Reviews: 70 - Favs: 206 - Follows: 271 - Updated: 1/5 - Published: 5/29/2022 - J. Keyes, J. Cutter, SPARTAN-B312/Noble Six, Jerome-092
Mass Effect Kills Halo by giblo126 reviews
I was frustrated and wanted to get something out.
Rated: K+ - English - Chapters: 1 - Words: 495 - Reviews: 28 - Favs: 2 - Follows: 2 - Published: 1/1
The Exiles:A New Power by Johnnieboy11 reviews
The beginning of the Battle For Earth signaled the start of the final, bloodiest campaign of the Human-Covenant War. Hastily, a plan is put into motion and an Ark Fleet, composed of a dozen Phoenix-class vessels and their escorts, makes the jump out of system. Either interference, or malfunction, causes their arrival to a new Galaxy, where new threats lurk just around the corner.
Rated: T - English - Sci-Fi/Adventure - Chapters: 6 - Words: 22,115 - Reviews: 130 - Favs: 534 - Follows: 815 - Updated: 12/28/2022 - Published: 12/26/2021 - OC, Tali'Zorah, Admiral Hackett, Rael'Zorah
Unknown events have unmeasurable answers by El callampas reviews
When someone contacts the Quarians about old machinery, they should think twice before engaging with a strange yet so familiar species, a war, and circumstances that will shock two galaxies now that the rift is open.
Rated: T - English - Sci-Fi/Drama - Chapters: 18 - Words: 161,181 - Reviews: 320 - Favs: 498 - Follows: 707 - Updated: 12/13/2022 - Published: 4/21/2022 - [Master Chief/John-117, Tali'Zorah] J. Cutter
No Greater Calling by silencewillfall0091 reviews
Because here's the thing. Turians, despite their reputations, had never loved war- not the suffering, the dying, nor the pain. They loved victory- the prevailing of clear good over clear evil- justice winning in the end, the beating of overwhelming odds for peace. And there was never more a clear example of this type of war than ours against the Covenant.
Rated: T - English - Sci-Fi - Chapters: 4 - Words: 6,957 - Reviews: 97 - Favs: 418 - Follows: 655 - Updated: 12/4/2022 - Published: 1/7/2022
Mass Effect: Forward Unto Dawn by WildcatWarrior67 reviews
Spartans never die. They're just missing in action. At least, that's how the saying goes. But for the Master Chief and Cortana, they're no longer missing. Awaking in a different universe, the two of them will uphold their oath: to protect Earth and all her colonies. Only it won't be from the Covenant this time. And just who is this Commander Shepard they'll be working with?
Rated: T - English - Sci-Fi/Adventure - Chapters: 3 - Words: 3,522 - Reviews: 20 - Favs: 100 - Follows: 180 - Updated: 11/28/2022 - Published: 11/26/2022 - Master Chief/John-117, Shepard
Mass Effect Terran Effect by The Grandiose Library reviews
Work In Progress
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 695 - Reviews: 3 - Favs: 29 - Follows: 38 - Published: 8/16/2022
Predating Prelates by Lighting wolf knight reviews
The one ship that ends up here and it changes so much... Rated T for violence, death, and profanity.
Rated: T - English - Adventure/Sci-Fi - Chapters: 1 - Words: 827 - Reviews: 3 - Favs: 7 - Follows: 12 - Published: 8/2/2022 - OC, Shepard, Peebee S.
Xen Effect by ThePilotArchangel reviews
Xen is the gateway between universes and dimensions. It is the place where time, space, physics, and other known rules that define ones life go out the metaphorical window. What will happen when a Child of Xen, a perfect Supersoldier, a Guardian of Humanity, and a Spectre of a Council of aliens find themselves caught up in a war of survival? Find out in "Xen Effect".
Rated: T - English - Sci-Fi/Adventure - Chapters: 8 - Words: 73,718 - Reviews: 40 - Favs: 97 - Follows: 123 - Updated: 7/4/2022 - Published: 4/30/2022 - Master Chief/John-117, Cortana, Shepard, OC
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 team comes 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! Chapters 6-22 Being Rewritten!
Rated: T - English - Adventure/Sci-Fi - Chapters: 49 - Words: 1,514,387 - Reviews: 901 - Favs: 429 - Follows: 406 - Updated: 6/14/2022 - Published: 6/21/2013 - Master Chief/John-117, Shepard - Complete
The Great Galactic War by hellothere45 reviews
Occurs after the events of Halo Infinite. Cortina finds out about a new enemy from the void of space called the reapers who are trying to rule the galaxy sending a warning to her former allies and enemies to unite the, she assigns chief espranza and the Weapon on a mission to unite the Citadel species to fight a war to end all wars in the Galaxy, can they do this task
Rated: T - English - Sci-Fi/Adventure - Chapters: 3 - Words: 4,068 - Reviews: 17 - Favs: 28 - Follows: 39 - Updated: 6/9/2022 - Published: 6/3/2022
Spirit of Fire by GoldenThorns-Fiverr reviews
A Crossover fanfic I did as a Fiverr request.
Rated: T - English - Chapters: 1 - Words: 7,853 - Reviews: 3 - Favs: 10 - Follows: 11 - Published: 5/24/2022 - Complete
Halo: A New Journey by mgarner3199 reviews
Master Chief wakes up in the Mass Effect universe and joins Commander Shepard in an effort to stop the Reapers. With time running out, can they stop the extinction of every species, or will they fade into legend?First, they got to stop the Reapers though...
Rated: K - English - Sci-Fi/Romance - Chapters: 3 - Words: 3,002 - Reviews: 15 - Favs: 37 - Follows: 73 - Updated: 4/27/2022 - Published: 12/7/2021 - Cortana, Master Chief/John-117, Illusive Man, Shepard
The voyage of Valiant by Lighting wolf knight reviews
There was more on the line... Yet plans and webs were made. Rated T for violence, death, and profanity.
Rated: T - English - Sci-Fi/Adventure - Chapters: 1 - Words: 811 - Reviews: 1 - Favs: 5 - Follows: 9 - Published: 4/20/2022 - Miranda K., D. Whitcomb, OC, Shepard
Noble Effect by LoneSpartan52 reviews
Noble Six was alone after the death of Emile. The Pillar of Autumn had left Reach, leaving the lone Spartan behind. But what if instead of dying on Reach, fighting to his last breath, Six survived? What if he escaped Reach and headed for Earth, only to end up in another galaxy, in another war? Will he agree to fight the reapers alongside aliens? Find out in Noble Effect
Rated: T - English - Sci-Fi - Chapters: 16 - Words: 62,375 - Reviews: 128 - Favs: 368 - Follows: 513 - Updated: 4/19/2022 - Published: 7/3/2020 - SPARTAN-B312/Noble Six, Garrus V., Shepard, Javik
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