Mass Effect 2 is an action role-playing video game developed by BioWare and published by Electronic Arts. It was released for Microsoft Windows and Xbox 360 on January 26, 2010, and for PlayStation 3 on January 18, 2011. Mass Effect 2 is the second installment of the Mass Effect series and a sequel to the original Mass Effect. The game takes place within the Milky Way galaxy during the 22nd century, where humanity is threatened by an insectoid species known as the Collectors. The player assumes the role of Commander Shepard, an elite human soldier who must construct and gain the loyalty of a diverse team in order to defeat the enemy in a suicide mission. With the use of a completed saved game of its predecessor, the player can impact the story of the game in numerous ways. Mass Effect 2 is set within the Milky Way galaxy during the 22nd century where interstellar travel is possible through the use of mass transit devices called Mass Relays, a technology claimed to have been built by an extinct alien race known as the Protheans. A conglomerate body of governments known as the Citadel Council controls a large percentage of the galaxy and is responsible for maintaining law and order among races of the galactic community. Races that belong to the Citadel Council include humans, asari, salarians, drell, and turians. Other alien races seen in the game include the reptilian krogan, the environmental suited quarians, and a hostile race of networked artificial intelligences called geth. During the events of the original Mass Effect, a geth army attempted to open a portal for a highly advanced machine race of synthetic-organic starships known as the Reapers. It is believed that the Reapers eradicate all organic civilization every 50,000 years. The galactic community has since lived in fear of another possible invasion. Meanwhile, a pro-human organization called Cerberus believes that humans deserve a greater role in the galactic community and supports the principle that any methods of advancing humanity's ascension are entirely justified, including illegal or dangerous experimentation, terrorist activities, sabotage, and assassination. As such, the Citadel Council has declared Cerberus to be a terrorist organization and will prosecute Cerberus agents accordingly.