After the end of War for Milda, System Alliance spent the next few years rebuilding the fleet. New classes of ships that fully hybridized the acquired technologies began to be produced at a tremendous pace, and System Alliance decided to resume expansion, but towards Unknown Regions, and not to known parts of the galaxy.(Sequel to - System Alliance: War for Milda)

Marcus thought he was done fighting after the death of Queen Myrrah, and the activation of the Imulsion Countermeasure. When he goes to help Baird investigate an abandoned COG facility, he will soon discover that while he ended one fight, another one has just begun.

This is a Mass Effect - Halo - XCOM Crossover. In the year 2084 during the Asteroid Belt Offensive XCOM Elite Unit Strike-1 discovers an Ethereal Station but must Psionic Teleport away but something goes wrong. In the Year 2552 the UNSC Fearless an Orion-Class Assault Carrier is forced to escape Reach under heavy fire, during the Slipsapce Transit something goes wrong.

There are universes that diverge from a choice and there are universes that are fundamentally different from one another, forming a vast, limitless multiverse. In these set of universes, there are orbs that manipulate and alter any reality, rip apart the boundaries between them. If left unchecked, they will bring an end of everything. Welcome to the multiverse. Enjoy your stay.

Gods, we thought ourselves to be with our galaxy secrets to be laid bare before us the galaxy quivered and the laws of reality bent to our will, we snuffed out fragments of the very cosmos itself fought wars that left nothing but stellar remnants and dust in replace of stars, With our domination all but certain. Until the echoes of subspace reached us and soon after continuedinside

In the Year 2015, Earth was attacked by an unknown Alien Empire. With X-com they fought the alien menace again and again, overcoming the Odds and Forging a new Empire comprised of the former enemies enslaved to the Elder's will. Now forged into an empire the likes of which the galaxy hasn't seen, they take their first steps into the great Unknown. Major Crossovers and OCs.

During the beginning of the Reaper War, Shepard is informed of a Prothean artifact claimed by Cerberus and sent to stop them. Little does he know is that soon, he will find himself and his crew in a world both familiar and alien to their own.

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?

See what happens when the reapers invade the Star Wars Galaxy! Can Commander Shepard, the Normandy Crew, and the Systems Alliance help rid this new galaxy of the reapers? Can the Republic and Separatist Alliance put aside their many differences for the good of the galaxy? Find out in: A War of Two Galaxies! (Takes place right before Revenge of the Sith. Slightly altered time line)

The Reaper invasion is nigh. Outnumbered and outgunned, the Citadel must turn to two new, dangerous allies for salvation: the Adeptus Mechanicus and Imperium of Man.

1 week before classes start again, team RWBY watched a report relaying to a strange light at Vale's industrial district, what they didn't know is that it would lead them to another dimension quite different from their own, and unwillingly trap themselves in this strange dimension. contains liberties with canon from both franchises and inevitable OCs.

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.

Emile survives the two zealots at the end of Reach, and after surviving Covenant onslaught, finds himself in the ME universe. Kick-ass picture is thanks to freejimmy on deviantart

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".

it was placed on him when he was born and he was never informed about it. but one day on the training field, he overloaded a seal that kept a secret from everyone in the village including himself. now that the seal is broken, he finds more about his ancestry and a new power that goes beyond his village. Gender bender of sorts. it will make sense if you give a chance

After the discovery of the Prothean ruins in 2128, the nations of the world formed the System Alliance as a military alliance against the alien threat. However, in 2137, the Lunar Incident threatened to fragment the alliance. However, a new discovery could spur the entire history of mankind. The game for mankind's survival has begun.

Matriarch Lantaya is a brave explorer from the Golden Age of Asari space exploration, and she wants to go home. The Lone Wanderer is a messianic cyborg from a world scorched in nuclear fire, and he wants to save the wastelands. Courier Six is a tribal postman who usurped control of an entire city state. He wants to eat people. Among other things. (Also available on Spacebattles)

ODST Captain Nathanial Renkov unintentionally becomes the first Helljumper to survive being dropped through a Slipspace anomaly. The problem? He has no idea where is and is surrounded by aliens the UNSC has no record of. Even worse? No one knows what the UNSC is. Follow his story as he tries to make sense of his new surroundings while trying to survive a new galactic threat.

Crow is stuck, but it's not all bad news; he's been offered shelter on the Normandy, and Spider can't hurt them here. Shepard now has an unkillable paracausal warrior, and his 'not-an-AI', Glint, is a complete cinnamon roll, but it's not all good news; he's half-starved, in culture shock, and has a bad case of trust issues. He might need work, sure, but who on this ship doesn't?

What was supposed to be the day of his greatest honor became the day of his greatest loss. Now in a world and a time he does not recognize, J'onn J'onzz must face a choice. He can easily hide himself and his abilities for his safety. Or, he can be what he was meant to be. A Manhunter.

Xavier Holmes, a simple programmer and over all shut-in was killed during a bank robbery. however, instead of staying dead he was reborn as an A.I and transported to the Star Trek universe. Xavier didn't how it was possible but one thing was clear he'd decide his own future. I do not own anything of Mass Effect or Star Trek.

Mankind endures. Twice have alien invaders attempted to force humanity into extinction. Twice they have failed. Now, an uneasy peace covers the galaxy as enemies both ancient and new slumber, or pace beyond the walls. The balance is about to tip. A discovery has been made on a Human colony, faces familiar yet strange move against them, and in the middle of it all, a name. Shepard.

A Citadel Exploration fleet filled with people the council didnt want around discovers something that will change the face of Citadel Space forever. The council will experience a crash course in the fight for survival (Reaper Incursion Arc)

Sequel of Unlimited Rettousei. Had you ever wondered what would happen if the Citadel council meet a species that all its members have powers like the Asari but different, has a stronger military like the Turian, and tech more advance than the Salarian. All that without element zero, but more importantly, they do not want to follow their orders.

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...