Mass Effect 3 (2012)
The first story, "Mass Effect," in the trilogy centers on a player-created character named Commander Shepard, with the mission to save the galaxy from a race of mechanical beings known as the Reapers and their followers, including Saren Arterius. "Mass Effect" sees Shepard facing Sovereign, a Reaper left as a vanguard, who plans to allow the Reaper fleet currently hibernating in extra-galactic dark space to invade the Milky Way, and destroy all sentient organic life, continuing a mysterious cycle of destruction. The second story, "Mass Effect 2," takes place two years later, and sees Shepard battling the Collectors, an alien race abducting entire human colonies in a plan to help the Reapers return to the Milky Way. The final stroy, "Mass Effect 3," of Shepard's trilogy centers on the final battle against the Reapers.
"Mass Effect 3" details the adventures of Systems Alliance Commander Shepard as they try to defeat a human-survivalist paramilitary group called Cerberus and a synthetic-organic race of machines known as the Reapers. The Reapers are immensely powerful and purge the galaxy of all advanced sapient life in 50,000 year cycles. In the Mass Effect 2 DLC Arrival, Shepard travels into Batarian space to rescue an Alliance deep cover agent named Dr. Amanda Kenson and learns that the Reaper invasion is imminent. To delay them, Shepard is forced to destroy a mass relay, obliterating the system and killing 300,000 Batarian colonists as collateral damage. Consequently, Shepard is ordered back to Earth with the Normandy impounded
"Mass Effect 3" begins on Earth with Commander Shepard having been detained following the events in Arrival. In the opening moments it is revealed that Earth has recently lost contact with its extra-solar assets and is hastily preparing for the imminent Reaper arrival. The assault comes moments later, and all of Earth's defenses are overwhelmed. Shepard escapes a burning Vancouver on the Normandy with the help of Admiral Anderson and either Kaidan Alenko or Ashley Williams (depending on which survived Virmire) and leaves to gather help from other species while Anderson coordinates human resistance on Earth. Before leaving the Sol System, Shepard is ordered to Mars by Admiral Hackett who claims that researchers have uncovered something that may give humanity a chance against the Reapers. There, Shepard battles Cerberus forces and encounters former squad-mate Liara T'Soni, who has discovered plans for a Prothean superweapon that may be capable of defeating the Reapers. Before leaving the facility, Shepard speaks with a now-hostile Illusive Man, who claims he wants to use the Prothean weapon to take control of the Reapers. Shepard pleads for help from the Council, but they are reluctant to oblige due to their own preoccupations and unwilling to bet everything on an untested device. Shepard realizes that the only way to gain other species' assistance will be to help them in their own wars against the Reapers and garner favors, while at the same time gathering war assets to be used against the Reapers in battle. Eventually, Hackett begins construction on the Prothean weapon and dubs it "The Crucible". ...
Did You Know? "Mass Effect's" ending received such a negative reception that the development studio postponed all planned Downloadable Content to develop and release the free "Extended Cut" DLC, which expanded upon the original endings.