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The Sword of the Geth by Doctor poo and the TURDIS reviews
Dying on Mantle's Approach, Cortana wakes up in an unfamiliar environment. In her drive to get home, she 'employs' the assistance of the local synthetics. She never wanted to be a galactic overlord. But a UNSC AI in an environment woefully unprepared for one of her caliber makes an easy one.
Crossover - Halo & Mass Effect - Rated: T - English - Sci-Fi/Humor - Chapters: 23 - Words: 123,604 - Reviews: 541 - Favs: 1,044 - Follows: 1,470 - Updated: 1h - Published: 11/23/2023 - Cortana, Shepard
Stellar Effect by Brandon Storm reviews
The Reapers trap was perfect in its design. Their execution refined over billions of years, their technology refined since the dawn of time itself. Right up until Someone Broke the Trap!
Crossover - Mass Effect & Stellaris - Rated: T - English - Adventure/Sci-Fi - Chapters: 71 - Words: 311,973 - Reviews: 281 - Favs: 405 - Follows: 527 - Updated: 3h - Published: 8/7/2022
Fall of the Citadel by Richard Scepton reviews
A fleet without an ocean, a humanity scarred forever by war. An admiral without a fleet, and a galaxy on the brink of war. It is the link in between, that will decide our fate, and that of the galaxy as a whole. CW: PTSD, depression, hand-to-hand combat and bayonets. Recommend not for children
Crossover - Mass Effect & Kantai Collection - Rated: T - English - Romance/Sci-Fi - Chapters: 14 - Words: 142,696 - Reviews: 78 - Favs: 86 - Follows: 129 - Updated: 7h - Published: 10/26/2023 - Shepard, Shigure, OC, Fubuki
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)
Crossover - Halo & Mass Effect - Rated: M - English - Adventure - Chapters: 17 - Words: 59,187 - Reviews: 138 - Favs: 485 - Follows: 724 - Updated: 19h - Published: 7/8/2022 - Rookie, Shepard
Star Mahou effect by phantompain12 reviews
Tanya finally winds up in mass effect after having dealt with Being X. Starkiller's son too ends up in mass effect after his own sacrifice to stop the empire. This is something like that. I have no idea what I am going to write. Author note: Guys, I don't know what the hell I am doing. I just decided to write and this is the result. Any help would be appreciated as Eng is 2nd lang.
Crossover - Star Wars & Mass Effect - Rated: T - English - Humor/Adventure - Chapters: 11 - Words: 24,184 - Reviews: 7 - Favs: 9 - Follows: 15 - Updated: 20h - Published: 1/30
Enthrallment Colors by undead3 reviews
Prince of the rogue human state, the Britannian Empire, Lelouch stumbles into grander conspiracies as he makes a bid for position within the Empire. Meanwhile Hana Shepard has been flung head first into a race against a renegade Spectre with the fate of all life in the balance. Are these two rising stars saviors, or destined to burn the galaxy in the flames of war?
Crossover - Code Geass & Mass Effect - Rated: M - English - Drama/Sci-Fi - Chapters: 12 - Words: 66,705 - Reviews: 31 - Favs: 37 - Follows: 46 - Updated: 23h - Published: 1/8 - Lelouch L., Kallen S., Shepard, Garrus V.
Robo Effect by Star Sage reviews
The Robotech wars are over. The survivors of Humanity and the Zentraedi are now alone in the universe, and so, come together, becoming something new, becoming Terrans. Now this race will find itself thrust into the galactic scene, as the Citadel Races and those beyond test these young upstarts, and in the shadows, old things begin to move.
Crossover - Robotech/Macross & Mass Effect - Rated: T - English - Sci-Fi/Adventure - Chapters: 64 - Words: 228,012 - Reviews: 640 - Favs: 912 - Follows: 987 - Updated: 2/2 - Published: 4/14/2015
Mario Effect by OroDeus
Haunted by visions of impending doom, Mario summons his ragtag team of explorers to adventure. Their journey across the stars will uncover the koopa king's horrible plot to take over the galaxy.
Crossover - Mario & Mass Effect - Rated: M - English - Sci-Fi/Adventure - Chapters: 4 - Words: 4,472 - Favs: 1 - Follows: 4 - Updated: 1/31 - Published: 12/27/2023 - Mario, Luigi, Daisy, Toad
Operation ECLIPSE - Apocrypha and Sidestories by HelenTheMoon
Omakes, sidestories and Apocrypha written by me and others for Operation ECLIPSE. The Sidestories are canon, the rest just for fun. Feel free to submit content yourselves! (I'll credit you, obviously)
Crossover - Sonic the Hedgehog & Mass Effect - Rated: T - English - Chapters: 6 - Words: 8,161 - Favs: 11 - Follows: 6 - Updated: 1/31 - Published: 12/25/2023
Operation ECLIPSE by HelenTheMoon reviews
Pre-ME1 post-Frontiers Xover, in which the Sonic version of Earth replaces ME Earth. A Batarian planet suddenly turns invisible, and things only get weirder from there. That poor STG agent won't know what hit him, that's for sure. And neither will the rest of the galaxy - once Sonic and Eggman get there. Crossposted on Spacebattles and AO3. Rating may change.
Crossover - Sonic the Hedgehog & Mass Effect - Rated: T - English - Sci-Fi/Fantasy - Chapters: 5 - Words: 51,951 - Reviews: 11 - Favs: 48 - Follows: 63 - Updated: 1/31 - Published: 11/26/2023 - Sonic, Tails, OC
Mobile Suit - Mass Effect: The First Contact War by Mister Smallville reviews
Two worlds collide, neither prepared for the other. The Solar Sphere Congress -successor to the long gone Earth Federation- unwittingly starts a galactic crisis when it makes first contact with a very angry, very trigger happy Turian Hierarchy.
Crossover - Gundam UC & Mass Effect - Rated: T - English - Sci-Fi - Chapters: 12 - Words: 74,722 - Reviews: 143 - Favs: 268 - Follows: 394 - Updated: 1/30 - Published: 8/7/2023
Never Fade Away by Ideas-Guy reviews
Lives are cheap and money is everything. That's how the orphanage made its money - lending out children for human expirementation. L is an old man at the age of fifteen and he knows he doesn't have much time left. All that mattered was getting out, but he soon learns that the world is a lot bigger than Night City. And that the galaxy is a lot bigger than Earth.
Crossover - Mass Effect & Cyberpunk 2077 - Rated: M - English - Adventure/Drama - Chapters: 52 - Words: 240,832 - Reviews: 371 - Favs: 1,116 - Follows: 1,243 - Updated: 1/29 - Published: 10/31/2022 - Shepard, V
Mortal Desperations by Solthrin reviews
Arcturus Magnus, Sagittarum of the Legio Custodes, has fought for years within the webway and the Impossible City. Upon taking a near-fatal wound, the Emperor Himself removes Arcturus from the front, sending him instead to bring forth reinforcements from the Mechanicum. When something goes wrong during the return, where does this Custodian find himself?
Crossover - Warhammer & Mass Effect - Rated: M - English - Sci-Fi/Adventure - Chapters: 9 - Words: 59,959 - Reviews: 118 - Favs: 520 - Follows: 759 - Updated: 1/28 - Published: 1/17/2023 - Adeptus Mechanicus, Tali'Zorah, Shepard
Boundaries Displaced by Hirowolfgang reviews
When a dormant Mass Effect is activated by Battarian pirates, it is affected by a mysterious phenomenon that displaces the Dreikruz en route to their final confrontation with the Quaestors. Now stranded Mitsuba and the Dreikruz have to put differences aside in order to work together with the Normandy SR-2 against the Collectors and the following Reaper war. For better or worse.
Crossover - Mass Effect & Super Robot Wars - Rated: M - English - Sci-Fi/Drama - Chapters: 9 - Words: 45,811 - Reviews: 17 - Favs: 37 - Follows: 55 - Updated: 1/28 - Published: 2/28/2023 - Garrus V., Shepard
Stellar Effect Codex by Brandon Storm reviews
A Codex exploring the History and Lore of the Stellar Effect Universe
Crossover - Mass Effect & Stellaris - Rated: T - English - Sci-Fi - Chapters: 17 - Words: 35,864 - Reviews: 28 - Favs: 44 - Follows: 44 - Updated: 1/28 - Published: 8/7/2022
Mass Effect demi humans by EclipsePheniox reviews
Long ago on earth demi-humans appeared on earth. Now expanding into the galaxy the other races have to deal with both humans and demi-humans. Mass effect story from beginning to end but with monster people to make it more interesting. Experimental, possible harem
Crossover - Mass Effect & Monster Girl Encyclopedia - Rated: M - English - Adventure/Sci-Fi - Chapters: 44 - Words: 150,440 - Reviews: 61 - Favs: 283 - Follows: 301 - Updated: 1/28 - Published: 8/2/2019
Asymmetry: A Tragedy in Ten Acts by Pseudomonus reviews
Almost 200 years after the Reapers' destruction, Commander Benezia Shepard is given a top secret mission: To explore a strange new universe; to seek out new threats and new enemies; to boldly go where no Asari has gone before! And, at the height of the Dominion war, the Federation facing defeat, Captain Forest encounters an unlikely ship that may hold the key to victory. Complete.
Crossover - StarTrek: Deep Space Nine & Mass Effect - Rated: M - English - Sci-Fi/Drama - Chapters: 12 - Words: 100,118 - Reviews: 21 - Favs: 26 - Follows: 36 - Updated: 1/28 - Published: 11/7/2023 - Complete
Imperial Warlord: Rewrite by deeed22 reviews
Two friends once cast adrift in a universe not their own find themselves in another. With their goals unknown, purpose not directed or forced, are they finally free to choose their own way?
Crossover - Warhammer & Mass Effect - Rated: M - English - Adventure - Chapters: 5 - Words: 19,885 - Reviews: 46 - Favs: 180 - Follows: 262 - Updated: 1/28 - Published: 8/30/2021 - Imperial Guard, OC, Adeptus Mechanicus
Feared Reverence by ayab reviews
376 years after the battle between heaven and earth. Two humans have achieved godhood. Using their power to guide humanity to the stars. How will the galaxy react to see a species so advanced yet so primitive? So powerful yet not wanting to use their power. They are what the citadel race aspires to be and hates because of their jealousy.
Crossover - Naruto & Mass Effect - Rated: T - English - Fantasy/Sci-Fi - Chapters: 27 - Words: 104,362 - Reviews: 193 - Favs: 326 - Follows: 438 - Updated: 1/26 - Published: 1/14/2023
Stellaris: Deja Vu by AdriannairdA reviews
When the Technocracy loses a science ship while exploring a nearby galaxy identical to the Milky Way, what first is a simple search and destroy mission becomes something much more complicated when it turns out, there are humans and other aliens there too. This'll be interesting... WARNING: Contains Plot Deviation and Shitty Dialogue
Crossover - Mass Effect & Stellaris - Rated: M - English - Sci-Fi/Adventure - Chapters: 2 - Words: 6,576 - Reviews: 7 - Favs: 21 - Follows: 29 - Updated: 1/26 - Published: 1/10 - OC
Cursed by Hookshot25 reviews
Clayton Carmine has only known hate and carnage for so many years. But once he survives the war he hoped to die in, things get strange. When people need help he isn’t one to shy away, and while helping Baird he gets sent to a place in dire need of a man like him. A man that can’t be claimed by death as easily as his kin.
Crossover - Gears of War & Mass Effect - Rated: M - English - Sci-Fi/Adventure - Chapters: 9 - Words: 133,327 - Reviews: 20 - Favs: 74 - Follows: 105 - Updated: 1/26 - Published: 4/10/2023 - C. Carmine, Samantha B./Sam, Shepard, Tali'Zorah
Bellum Terranum by F35B reviews
Humanity has long since recovered from the effects of the Human-Covenant War, beginning to resettle and rebuild. The Quarians, with help from the Council, have also begun to rebuild their fallen civilization, settling pre-approved Council planets finally settling after surviving the Morning Wars. However, one of these planets has already been taken by an unaware humanity.
Crossover - Halo & Mass Effect - Rated: T - English - Sci-Fi/Adventure - Chapters: 2 - Words: 15,221 - Reviews: 171 - Favs: 400 - Follows: 612 - Updated: 1/25 - Published: 7/31/2023
The mark of the federation of independent species by migos501 reviews
(TESTING PHASE)“A single event can shape our lives or change the course of history.” United under a single banner, the federation stands as a testament that any species can thrive in harmony, gifted with technology that can tip the scale of an entire galaxy, they now face with a entirely new government and it’s sets of challenges(focusing on the mass effect story)
Crossover - Halo & Mass Effect - Rated: M - English - Sci-Fi - Chapters: 2 - Words: 37,073 - Reviews: 32 - Favs: 70 - Follows: 83 - Updated: 1/24 - Published: 10/6/2023 - Master Chief/John-117, Shepard
The Effect of a Horse and a Dragon by Vimesenthusiast reviews
A different decision right after being cursed leads to a very different Ranma showing up in Nerima. When he goes after Herb to beat some sense into him Ryoga takes the chance to get rid of his rival once and for all, sending both combatants to the Mass Effect universe. What changes will two martial artists and their use of ki have on the coming conflict? RanmaXTaliXKasumiXSama
Crossover - Ranma & Mass Effect - Rated: M - English - Humor/Adventure - Chapters: 8 - Words: 160,443 - Reviews: 599 - Favs: 2,239 - Follows: 2,311 - Updated: 1/23 - Published: 2/2/2014 - Ranma, Kasumi G., Tali'Zorah, Samara
Judgement Effect by The Dullahan of Lore reviews
Having been cast into the ME-verse; Xander was 'saved' by a rogue scientist who took advantage of subconscious memories for the creation of A.I. Xander was transformed. he became...Skynet. YAHF!Xander. Rated M just in case at this point.
Crossover - Buffy: The Vampire Slayer & Mass Effect - Rated: M - English - Sci-Fi/Drama - Chapters: 4 - Words: 10,581 - Reviews: 19 - Favs: 84 - Follows: 116 - Updated: 1/20 - Published: 12/20/2023 - Xander H., Benezia
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