XCOM: Mass Effect

Synopsis: Humanity has successfully destroyed ADVENT and the Elders. As humanity rejoices, the newly formed Union looks to the stars. It is unavoidable, then, that the Union would eventually meet with the Citadel.

Chapter 1: Timeline

March 2015: Humanity is attacked by extraterrestrial life forms known as the Elders. The XCOM Project is initiated by the Council.

November 2015: After a bloody and fruitless 8-month campaign against the invaders, the Council surrenders and betrays XCOM, which leads to a siege on the XCOM base. The base is completely destroyed and all research in alien technology is lost. The Commander, Doctor Vahlen and several other personnel go missing. However, several researchers and engineers escape, with Dr. Raymond Shen amongst them. Only the Spokesman, a mysterious Council member, remains loyal and becomes a mole in ADVENT. The short-lived First Contact War ends.

December 2015: Now under the control of the aliens, the aliens form the ADVENT Coalition and assumes the position of Earth's government. While seemingly benevolent, they carry out subversive activities against people in the know of their activities and secretly abduct civilians in the Avatar Project.

February 2016: The Resistance is formed, and XCOM captures an alien supply craft, which is converted into their mobile base. 3 weeks later, Raymond Shen dies and his daughter Lily Shen takes over the Engineering department of XCOM.

October 2016: The systems aboard the mobile base, now named the Avenger, is successfully modified for XCOM's use. The onboard Elerium Core goes online and the ship has an independent power source. XCOM begins recruiting soldiers, engineers and research staff. The Skyranger is rebuilt using alien technology to increase its efficiency.

June 2017: Dr. Richard Tygan, disillusioned with ADVENT, escapes the ADVENT controlled cities and is recruited by XCOM.

March 2035: The Commander is tracked to an ADVENT facility, which is attacked by XCOM, and they successfully escape with the Commander. It is also revealed that ADVENT has a psionic network for data exchange between soldiers and that the Commander had been used as a battle simulator when connected to the network due to his great strategic skill. The Avatar Project is revealed to XCOM, but its contents remains mostly mysterious.

December 2035: The first Psi Lab is built on the Avenger and is used to test for soldiers with Psionic potential.

February 2036: The first Psi Operative, Yui Tachibana, is discovered.

August 2036: During an attack on an ADVENT facility to stall the completion of the Avatar Project, the soldiers encounter a prototype Avatar. After much difficulty, the Avatar is killed and is transported back to the Avenger.

March 2037: At this point in time, there are 5 other Psi Operatives.

April 2038: Through the raid on an ADVENT facility, Tygan and Shen recover sufficient data to conclude that the Elders, the leaders of ADVENT, have been slowly dying from an irreversible physical degeneration of their bodies. In order to escape their imminent demise, the Elders started the Avatar Project, which involves processing kidnapped humans and turning them into raw material to build new bodies for themselves, called Avatars.

December 2038: The Avenger's systems are disrupted by an ADVENT craft. XCOM soldiers fight off all hostile forces and escape onboard the Avenger.

May 2039: Tygan and Shen track the Elders' headquarters to an underwater base, accessible only by a special psionic portal. With their hand forced, ADVENT decides to accelerate the project and process all "non-essential" humans into the Avatar project, under the guise of curing all disease at their gene clinics.

September 2039: The Spokesman sacrifices himself to warn XCOM about the plan, ordering them to hijack ADVENT's global communication network before they can make the announcement. XCOM manages to hack the network and transmits proof of ADVENT's crimes to the entire world, causing a mass global revolution. The Elder Revolution begins.

December 2039: With ADVENT busy trying to maintain order, XCOM successfully clones their own Avatar, under the control of the Commander, and stages a raid on the Elder headquarters. The Elders plead with the Commander to stop the fighting and rejoin them, claiming that they are only trying to strengthen themselves and humanity against a greater threat. The Commander ignores the Elders' pleas and destroys all of their Avatars, triggering the destruction of the base. The Commander's Avatar stays behind to battle the enraged spirits of the Elders as the rest of the squad escapes.

February 2041: Humanity destroys ADVENT with the assistance of XCOM. Remaining ADVENT forces are secretly executed by XCOM en masse, and their corpses are scrapped for materials and are incinerated. The Elder War ends.

March 2042: The Union is created and acts as Earth's government. XCOM becomes the Union's main military force and becomes a primary response force towards hostile alien forces and to enforce law on Earth. Rebuilding commences.

July 2044: Humanity uses alien UFO designs to create their own aircraft, the Firestorm. Variants are created for special purposes. Tygan wins the Nobel Prize for the discovery of the contents of both Elerium and Alien Alloys, now named Vahlenite to honour the missing Dr. Vahlen. Rebuilding is at 50% completion. Artificial gravity is discovered and the technology onboard alien ships and ADVENT facilities is shown to be capable of FTL by warping space and time to form wormholes to travel extremely long distances. However, this is considered to be unfeasible due to the energy cost of such a device. Such devices are known as Bridge Drives.

April 2046: Rebuilding of Earth is completed.

May 2061: Humanity reaches the moon and discovers the ADVENT remnants and a still-alive elder in an Avatar. The Union announces a state of emergency and the moon becomes a battlefield. The Battle for Luna commences.

December 2062: The moon is recaptured and all corpses and alive ADVENT forces are taken in for experimentation. Several missing humans are discovered, such as Dr. Vahlen and several prominent scientists. The original, unmodified variants of the invading force is discovered and cryogenically unfrozen. The moon is renamed Luna and a military installation is built and is called Lunar Base Alpha. Construction of a Union military fleet begins at the shipyard of Lunar Base Alpha. Ships are grouped into different ship classes. Research into more efficient and cheaper Elerium Cores begin.

August 2070: After a long and tedious experimentation period, a translator was formed with the help of Yui Tachibana and several other Psi Operatives. The aliens reveal that their worlds were conquered and they were forced into servitude with Psionic control by the Elders. Sectoids are known as good engineers, and the Mutons' strength allows them to aid in the construction of new Union facilities and spacecraft. Cyberdiscs and drones, prototypes to Gatekeepers, become programmers and are regular sights in Union intelligence task forces. They are integrated into human society with little to no trouble.

September 2075: Dr. Richard Tygan passes away and a memorial is erected. The Tygan Institute of Science is formed. Later this year, they use Andromedon and ADVENT MEC designs to create combat drones, driven by AIs, which are designed by Cyberdiscs. Andromedons no longer require coolant are are heavily armoured, whereas MECs now have plasma cannons.

June 2089: The GREMLIN MK XIV is developed, with a new processor that can process a few hundred terabytes per second, much to the delight of Specialist-class soldiers. The new GREMLIN have a small plasma pistol attached. Research into cores is completed, and all Union ships are outfitted with Bridge Drives.

May 2089: In a Union project, a Cyberdisc and several humans create code and integrate it into a GREMLIN, which causes it to become sentient, making it a true Artificial Intelligence. Public opinion is unexpectedly positive, and the GREMLINs are subjected to the Right of Sentient Entities Act, which gives civil rights to all sentient entities.

April 2091: As 80% of the population is Psionic, the results of a Union research project on Psionics is released publicly. It is revealed that Psionics live twice as long as normal humans. This revelation enforces the concept that Psionics are humans that are on a higher level of evolution.

July 2091: When a Union Avenger-class craft, the Architect lands on Mars, they discover an alien base. XCOM mobilises, but the base is found to be completely empty. Scientists scavenge the base for technology and data. However, the technology and architecture of the base is completely non-Elder, which leads the scientists to believe that the now-termed Protheans, were ignored by the Elders due to their military strength, as evidenced by several star maps discovered on the base. The technology is based off a substance known as Element Zero as it has zero mass. The passing of an electric current through it allows it to release dark energy which can be manipulated into a mass effect field, a phenomenon that can raise or lower the mass of all objects within that field. A positive current increases mass, a negative current decreases it. This "mass effect" can be used in countless ways, from generating artificial gravity to manufacturing high-strength construction materials. However, they are thought to be unnecessary as FTL drives already exist. The possibility of time dilation with the use of FTL Element Zero drives whereas the instantaneous nature of Bridge Drives make Bridge Drives a better option.

May 2100: Mars and Luna now have thriving human cities, and a project to terraform Mars begins.

August 2109: A human science team exploring the edge of the system near Pluto discovered that Charon was not a moon at all, but an enormous piece of ancient technology known as a mass relay that had been used by the Protheans. The discovery was not completely surprising, however, since the Prothean ruins found on Mars in 2091 had mentioned such a device. While the scientific theory behind the creation of mass relays was still beyond humanity's reach at the time, scientists were able to reactivate the dormant relay.

Exploratory probes sent through the Charon Relay immediately dropped out of contact, and it was determined that the only way to learn what was on the relay's other side was to send actual explorers through and as it was unable to determine the distance, Bridge Drives were unusable. Led by Jon Grissom, a team of brave men and women willing to risk their lives traveled through the relay, and discovered that it led to Arcturus. Their successful return made them heroes, and humanity entered a new age of unparalleled discovery and expansion. The Charon Relay, however, is rendered unnecessary as the estimated distance between Charon and Arcturus was calculated, and can now be accessible via Bridge Drives.

April 2140: The Tygan Institute of Science sends several ships into a nearby Mass Relay to further experiment with a Element Zero. However, they accidentally trigger the relay and appear near another relay. They are mysteriously destroyed and the Second Contact War begins.

Edit: I modified some of the typos I've made.