Halo and Mass Effect Crossovers
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Collectors at Dawn by jacksld850 reviews
The Master Chief and Cortana find themselves in an alternate reality and in contact with a mysterious black ops organization. Events soon spiral out of their control as they're forced into another battle for another humanity's survival.
Rated: T - English - Adventure/Sci-Fi - Chapters: 11 - Words: 49,277 - Reviews: 39 - Favs: 173 - Follows: 264 - Updated: 2h - Published: 1/20 - Master Chief/John-117, Cortana, Miranda L., Shepard (M)
A Dark Rising by RedShirt1453 reviews
It has been 35 years since the end of the First Contact War. Humanity has won through the means of a great discovery and now controls most of the known galaxy. But with this victory came disease, a victor's disease that rots humanity to its core. This corruption has spread to every fabric of its society turning the victors, into monsters. It cannot be stopped, but can we survive?
Rated: T - English - Adventure/Sci-Fi - Chapters: 18 - Words: 84,428 - Reviews: 121 - Favs: 72 - Follows: 87 - Updated: 5/25 - Published: 11/7/2016
The Cycle by Church 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: 40 - Words: 114,912 - Reviews: 124 - Favs: 55 - Follows: 69 - Updated: 5/25 - Published: 8/29/2012 - Arbiter, Prophet of Truth, Shepard (M), OC
Peace in Our Time by silencewillfall009 reviews
The Forerunner/Human union of the RIS rises to challenge the Citadel Council. Another superpower has risen. And they will claim their rightful place in the galaxy. Constructive criticism welcome.
Rated: T - English - Sci-Fi/Adventure - Chapters: 7 - Words: 5,591 - Reviews: 71 - Favs: 140 - Follows: 220 - Updated: 5/22 - Published: 3/23
The Reclamation has already begun by Fade Maybe reviews
The Master Chief has defeated the Didact. Across the galaxy, the Reaper War wages on as the Citadel races struggle to survive while Commander Shepard and the crew of the SSV Normandy fights on. But a deeply divided UNSC discovers a Mass Relay that will change the course of the war and galactic history forever. The Reclamation has already begun. And we are hopeless to stop it.
Rated: T - English - Adventure/Sci-Fi - Chapters: 20 - Words: 220,213 - Reviews: 627 - Favs: 676 - Follows: 879 - Updated: 5/22 - Published: 3/13/2013
Mass Effect - The Great Journey by ImperialSalesman reviews
Commander Shepard had failed. The Cycle continued, as planned. Now, the last cycle's failure will be the next cycle's trial, as the Great Journey draws ever near. Fighting against powers far beyond his own abilities, it is now up to Shipmaster Thel 'Vadamee to halt the return of the galaxy's most ancient foes, as dark powers work against everything he holds dear. (Halo AU)
Rated: T - English - Sci-Fi/Adventure - Chapters: 8 - Words: 30,314 - Reviews: 10 - Favs: 34 - Follows: 43 - Updated: 5/15 - Published: 2/3 - Arbiter, Rtas 'Vadumee, R. Moramee, Shepard (F)
HaloEffect: Rise of The Republic by Fernix13 reviews
When Great War ended, humanity and covenant merged. New formed Republic of Orion Arm is trying to create a war-free civilization, but what will happen when this empire will meet another galactic goverment? Rated T for blood, death etc. Multiverse crossover (Cancelled)
Rated: T - English - Sci-Fi - Chapters: 9 - Words: 18,198 - Reviews: 85 - Favs: 296 - Follows: 358 - Updated: 5/14 - Published: 8/24/2015
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: 19 - Words: 39,822 - Reviews: 92 - Favs: 62 - Follows: 76 - Updated: 5/14 - Published: 1/15/2015 - Gravemind
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: 19 - Words: 171,269 - Reviews: 126 - Favs: 239 - Follows: 288 - Updated: 5/8 - Published: 5/3/2016 - Master Chief/John-117, Cortana, Admiral Hackett, Shepard (M)
What Is It Worth? by The Best of Luck reviews
Humanity has known the Citadel Alliance for over six decades. After sixty years of isolation and limited contact, the UNSC have decided to open up more. When a joint dig at a Prothean site goes wrong, Commander Shepard will lead a mixed team consisting of the best the galaxy has to offer, regardless of their species, after one of the greatest enemies humanity has ever faced.
Rated: T - English - Sci-Fi/Adventure - Chapters: 2 - Words: 6,438 - Reviews: 5 - Favs: 59 - Follows: 86 - Updated: 5/7 - Published: 2/12
A Dark Occupation by RedShirt1453 reviews
Thessia has fallen and is now shadowed under the banner of the UNSC Eagle. Humanity rules the Asari homeworld with an iron fist. There are many stories that can be told during this dark time. Here are a few from those who were there, accounts from both Human and Asari, Soldier and Civilian, Freedom fighter and Collaborator. (Side Story Prequel to A Dark Rising).
Rated: T - English - Tragedy - Chapters: 7 - Words: 7,912 - Reviews: 35 - Favs: 28 - Follows: 32 - Updated: 5/3 - Published: 1/19
The Avalon Federation Codex by DragonheartODST reviews
A full codex dedicated to the characters, cultures, places, objects, times, etc., related to the Concordian Cycle starting from Book One: Dawn of a New Age. Will be constantly updated alongside the books to fit with the details of the series. Please read the series first if you wish to gain a greater understanding.
Rated: T - English - Sci-Fi - Chapters: 5 - Words: 34,711 - Reviews: 28 - Favs: 20 - Follows: 18 - Updated: 5/1 - Published: 11/30/2016
What the Hell! by TheDreadCaptain reviews
The UNSC colony of Avalon is under attack by Citadel forces just before a Covenant crusire arrives. AU set in the opening years of the Human-Covenant war. UP FOR ADOPTION.
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 1,050 - Reviews: 6 - Favs: 10 - Follows: 18 - Published: 4/30
Massive Halo Impact Codex AU by SPARTAN-III G-141 reviews
just a codex I made that anyone can use, but to add things must be verified by me
Rated: T - English - Sci-Fi - Chapters: 1 - Words: 2,146 - Reviews: 5 - Favs: 2 - Follows: 3 - Updated: 4/26 - Published: 4/24 - OC, OC
Of The Future And Past by IAnswerToNoOne reviews
The UNSC/Covenant war is over. The UNSC, Covenant, and Prometheans have joined to create the Republic of Sentient Species and are now an almost galaxy-wide power. Still, with the discovery of a device in space, and learning of a new enemy, will the RSS be able to react in time?
Rated: T - English - Adventure - Chapters: 9 - Words: 20,876 - Reviews: 97 - Favs: 229 - Follows: 315 - Updated: 4/15 - Published: 10/1/2016
Halo New Galaxy by Commander Kelec reviews
In 2554 the UNSC made contact with the Citadel races. But not everyone wants peace. Is cooperation between the UNSC and Citadel possible against the ex-Covenant splinter factions or will it turn into a three way war. ODST Lt Colonel John Shepard and Spartan Fireteam Crimson is right in the middle of it.
Rated: T - English - Sci-Fi/Adventure - Chapters: 18 - Words: 54,175 - Reviews: 43 - Favs: 65 - Follows: 86 - Updated: 4/12 - Published: 11/21/2016 - Garrus V., U. Wrex, Shepard (M)
Balaho Effect: Covenant War by TheDreadCaptain reviews
This is the sequel to Balaho Effect by Oledom, Unggoy Will Rain supreme and the Council WILL fall. But during all the battles, during all the death, an old evil awakens... its not the flood.
Rated: T - English - Adventure/Sci-Fi - Chapters: 1 - Words: 1,447 - Reviews: 5 - Favs: 23 - Follows: 28 - Published: 4/12
Balaho Effect by Oledom reviews
In the Year 2142, Unggoy explorers on Buwan discovered the remains of an ancient spacefaring civilization. They called it the greatest discovery in Unggoy history The civilizations of the galaxy call it. Mass Effect
Rated: T - English - Sci-Fi/Humor - Chapters: 9 - Words: 14,150 - Reviews: 51 - Favs: 107 - Follows: 115 - Updated: 4/11 - Published: 1/28
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.
Rated: T - English - Sci-Fi/Adventure - Chapters: 33 - Words: 309,896 - Reviews: 2573 - Favs: 2,866 - Follows: 3,484 - Updated: 4/6 - Published: 10/9/2013 - Master Chief/John-117, T. Lasky, Admiral Hackett, Shepard (M)
The Endurance of War by BulletstormX reviews
War is the only outcome to decide who is right. Battles can change a person for the rest of there life. Three different armies will have to work together to fight against all odds. Not my best summary, but will have to do.
Rated: T - English - Sci-Fi - Chapters: 3 - Words: 2,341 - Reviews: 6 - Favs: 34 - Follows: 40 - Updated: 4/2 - Published: 3/26 - E. Anders, J. Cutter, D. Anderson, Shepard (F)
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: 26 - Words: 243,879 - Reviews: 932 - Favs: 1,515 - Follows: 1,939 - Updated: 3/30 - Published: 3/27/2011 - Master Chief/John-117, Tali'Zorah, Miranda L., Shepard (M)
Halo Wars 2 X Mass Effect X Star Wars by BulletstormX reviews
Read for more if interested in.
Rated: T - English - Sci-Fi - Chapters: 5 - Words: 851 - Reviews: 16 - Favs: 4 - Follows: 3 - Updated: 3/26 - Published: 2/22 - J. Cutter, E. Anders, D. Anderson, Garrus V.
Catalog of War by hunter 139 reviews
A collection of one shots about events, including battles, conflicts and skrimishes, that occur in the shared multiverse of my stories. I do not own any of the franchises that appear in this series. Multicrossover.
Rated: T - English - Sci-Fi - Chapters: 10 - Words: 16,295 - Reviews: 7 - Favs: 10 - Follows: 8 - Updated: 3/26 - Published: 4/21/2015
The Unknown Defender by Gabenator5 reviews
Whilst Shepard is closing in on Saren, rumors begin to spread among the Pirates and Slavers of the galaxy. Rumors of a nameless fear. of A creature, A Demon Wreathed in Green Armor. It and its allies appear from nowhere and stop their raids on Defenseless Colony Settlements. Slaughtering every Single Attacker... and then Vanishing without a trace. Who or What is this... Thing.
Rated: T - English - Adventure/Sci-Fi - Chapters: 14 - Words: 90,345 - Reviews: 603 - Favs: 1,331 - Follows: 1,776 - Updated: 3/22 - Published: 9/27/2016 - Master Chief/John-117, Cortana, Shepard (F)
Pathfinder by Andrithir reviews
Alone and adrift in Andromeda, the crew of the Hyperion find themselves in the war fought between a ferocious theology and the UNSC, a human faction that is different and yet unnvervingly similar to the Systems Alliance.
Rated: T - English - Sci-Fi/Adventure - Chapters: 1 - Words: 2,722 - Reviews: 43 - Favs: 134 - Follows: 216 - Published: 3/22 - Master Chief/John-117, Scott R.
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