Halo and Mass Effect Crossovers
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A Whole New World by Spartan III Commando reviews
Noble six's story did not end on Reach, he escaped the doomed planet after saving the Pillar of Autumn, and he and 117 fought across each Halo, until an incident sent him to a whole new world. And he is wholly unprepared for the journey in store.
Rated: M - English - Sci-Fi/Adventure - Chapters: 9 - Words: 35,995 - Reviews: 54 - Favs: 281 - Follows: 411 - Updated: 2/18 - Published: 7/7/2016 - SPARTAN-B312/Noble Six
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: 5 - Favs: 29 - Follows: 43 - Updated: 2/16 - Published: 2/9 - Illusive Man, Shepard
The Rook by Twisted Fate MK 2 reviews
On the way down to New Mombasa, Rookie falls into the Slipspace Rupture and ends up crashing down on Menae, high above Palaven, right in the midst of the Reaper War. From there, the war itself will shift and the fighting persists, but who knows what an ODST will add to the mix. (Redo of an older story)
Rated: M - English - Adventure - Chapters: 10 - Words: 36,153 - Reviews: 82 - Favs: 323 - Follows: 493 - Updated: 2/16 - Published: 7/8/2022 - Rookie, Shepard
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. Crossposted by myself, Jabber the very wocky on Ao3.
Rated: T - English - Drama/Sci-Fi - Chapters: 2 - Words: 13,882 - Reviews: 56 - Favs: 178 - Follows: 249 - Updated: 2/15 - Published: 2/11 - Master Chief/John-117, Miranda K., Cortana
Drop into Hell by Lighting wolf knight
They have a lot more to do before its done. Rated T for violence, death, and profanity.
Rated: T - English - Adventure/Romance - Chapters: 2 - Words: 5,426 - Favs: 11 - Follows: 16 - Updated: 2/10 - Published: 2/3 - Miranda K., OC, Admiral Hackett, Shepard
The USSC: A Timeline by SimplyLaggy reviews
A timeline of my USSC fanfic base, and a smol teaser to two upcoming fics
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 1,615 - Reviews: 2 - Favs: 8 - Follows: 7 - Published: 2/8
Lost Son of Terra Phoenix by Ares007 reviews
For eons past, they enjoyed the harvest of their farms. Countless civilizations breathed life because they allowed it. Now, they will die because he demands it. Halo/Mass Effect but with heavy elements from Warhammer 40k. M-Shep/Miranda, OC/Liara. HFY
Rated: M - English - Adventure/Romance - Chapters: 16 - Words: 116,869 - Reviews: 47 - Favs: 153 - Follows: 197 - Updated: 2/8 - Published: 11/29/2021 - [SPARTAN-B312/Noble Six, Oriana L.]
HALO x ME: The Relay by SimplyLaggy reviews
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: 24 - Follows: 32 - 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
Galactic Conflicts: Tales of First Contact by TheDoctor1998 reviews
Humanity and its allies have stood strong after the Great War with the Covenant. Follow the Systems Alliance as it goes through its various first contacts.
Rated: M - English - Sci-Fi - Chapters: 1 - Words: 7,667 - Reviews: 10 - Favs: 42 - Follows: 65 - Published: 2/6
War of the Old Ones by Ian the Mechanic reviews
In forgotten ages past, two near eldritch forces vied for the very life essence of the Galaxy. Unknown to the young races, that war is still ongoing. how can the UNSC, the Citadel Council or the Covenant hope to stand against such forces, when they are still embroiled in their own petty squabbling? How could they hope to survive the War of the Old Ones?
Rated: M - English - Sci-Fi/Horror - Chapters: 16 - Words: 85,802 - Reviews: 97 - Favs: 199 - Follows: 296 - Updated: 2/6 - Published: 2/21/2022
United Earths Empire Rewrite 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: M - English - Adventure/Fantasy - Chapters: 2 - Words: 11,294 - Reviews: 12 - Favs: 102 - Follows: 122 - Updated: 1/31 - Published: 1/5
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: 43 - Words: 744,890 - Reviews: 1231 - Favs: 1,702 - Follows: 2,048 - Updated: 1/23 - Published: 6/8/2018 - SPARTAN-B312/Noble Six, Rookie
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: 94 - Follows: 156 - 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: 205 - 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: 26 - Favs: 1 - 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: 523 - Follows: 802 - Updated: 12/28/2022 - Published: 12/26/2021 - OC, Tali'Zorah, Admiral Hackett, Rael'Zorah
Mass effect: the Jaded ones by Ray SK reviews
A UNSC Human-covenant war-era battle group led by a Punic class supercarrier is introduced to a new galaxy. One where people are xenophilic, use to times of peace and harmony, and against disrupting the Status Quo. What will an extremely aggressive xenophobic and battle-hardened human faction add to the mix? and will their addition change the future of this galaxy. (No Spartans)
Rated: M - English - Adventure/Humor - Chapters: 5 - Words: 29,851 - Reviews: 69 - Favs: 166 - Follows: 249 - Updated: 12/25/2022 - Published: 2/6/2022 - E. Buck, OC
A Galaxy of Inheritors and Usurpers by HaloZealotDemon reviews
The Separatists destroy the Covenant in a brutal war, yet in the 2570s they persist in their efforts, but in two years they will be gone. However The Gods have other plans. The Migrant fleet decides that to escape through Relay 314 to unknown space, but meet, as LTCOL Church said "Sleep-deprived Titans with negative zero fucks to give." Heavy AU, Rvb elements, swearing.
Rated: M - English - Sci-Fi/Drama - Chapters: 1 - Words: 4,788 - Reviews: 20 - Favs: 133 - Follows: 181 - Published: 12/25/2022 - Arbiter, T. Hood, Tali'Zorah, Councilor Sparatus
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: 319 - Favs: 486 - Follows: 699 - 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: 403 - Follows: 636 - 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: 94 - Follows: 169 - Updated: 11/28/2022 - Published: 11/26/2022 - Master Chief/John-117, Shepard
Collectors at Dawn v2 by jacksld850 reviews
A rewrite of the original Collectors at Dawn. Lost all of the work I had on it so I'll be redoing it from scratch.
Rated: M - English - Adventure/Sci-Fi - Chapters: 1 - Words: 11,710 - Reviews: 4 - Favs: 31 - Follows: 58 - Published: 11/21/2022 - Master Chief/John-117, Cortana, Miranda L., Shepard
The Adventures of the Lucen: The VykurCorp Conspiracy by General Rage reviews
Liara T'Soni continued her mission to protect the Galaxy while Commander Shepard is in another dimension. She must stop the Covenant and the allies they've gathered from wreaking havoc in a Galaxy without it's greatest hero. While she's had some success, there's a gathering storm on the horizon and one of her crew of misfits will be forced to confront her past before it clears.
Rated: M - English - Sci-Fi/Adventure - Chapters: 15 - Words: 249,270 - Reviews: 174 - Favs: 132 - Follows: 138 - Updated: 11/17/2022 - Published: 6/26/2016 - OC, Liara T'Soni, U. Wrex
Were it So Easy by Sigma0327 reviews
Six's life was a giant war. Every battle was a test of sheer tenacity and stubbornness against insurmountable odds. Every moment, every bullet fired, every Covenant, Insurrectionist, and Flood spore killed has led up to his last fight. Once again he was one of the few that stood between Earth and her enemies. This would be his final battle, and nothing could change that, right?
Rated: M - English - Adventure/Sci-Fi - Chapters: 8 - Words: 98,545 - Reviews: 158 - Favs: 776 - Follows: 1,099 - Updated: 11/11/2022 - Published: 11/9/2020 - SPARTAN-B312/Noble Six, Tali'Zorah, Miranda L., Shepard
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