Mass Effect 2 is an action role-playing video game developed by BioWare and published by Microsoft Game Studios and Electronic Arts for Windows and Xbox 360 in 2010 and published by Electronic Arts for PlayStation 3 in 2011. It is the second installment in 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 alien race known as the Collectors. The player assumes the role of Commander Shepard, an elite human soldier who must assemble and gain the loyalty of a diverse team to stop the Collectors in a suicide mission. Using a completed saved game of its predecessor, the player can impact the game’s story in numerous ways.

For the game, BioWare changed several gameplay elements and further emphasized third-person shooter aspects, including limited ammunition and regenerable health. In contrast to the exclusive focus on the main story of the original Mass Effect, the developers opted to create a plot where optional missions had as much intensity as the main mission. Mass Effect composer Jack Wall returned to compose Mass Effect 2’s music, aiming for a darker and more mature sound to match the game’s mood. Mass Effect 2 also supports a variety of downloadable content packs, ranging from single in-game character outfits to entirely new plot-related missions. Notable packs include Kasumi – Stolen Memory, Overlord, Lair of the Shadow Broker, and Arrival.

Mass Effect 2 is a single-player action role-playing game in which the player takes the role of Commander Shepard from a third-person perspective. Before the game begins, the player determines Shepard’s gender, appearance, military background, combat training, and first name. The player may choose to import a character from a completed saved game of the original Mass Effect or start the game with a new character. Importing an old character allows several decisions the player made in the original game to impact the story of Mass Effect 2 and grants the player a set of starting bonuses. The game features six different character classes for the player to choose from. Each class is proficient in a different set of powers and weapon types. For example, the Vanguard class specializes in close-range combat and shotguns, while the Infiltrator class relies on stealth combat and sniper rifles.