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https://en.wikipedia.org/wiki/System_Shock_2
System Shock 2 is a first-person shooter action role-playing survival horror video game for Microsoft Windows, OS X and Linux, designed by Ken Levine and co-developed by Irrational Games and Looking Glass Studios. Originally intended to be a standalone title, its story was changed during production into a sequel to the 1994 PC game System Shock; the alterations were made when Electronic Arts—who owned the System Shock franchise rights—signed on as publisher. System Shock 2 was released on August 11, 1999, in North America.
The game takes place on board a starship in a cyberpunk depiction of 2114. The player assumes the role of a soldier trying to stem the outbreak of a genetic infection that has devastated the ship. Like System Shock, gameplay consists of combat and exploration. It incorporates role-playing system elements, in which the player can develop skills and traits, such as hacking and psionic abilities.
System Shock 2 received positive reviews, but failed to meet commercial sales expectations. Many critics later determined that the game was highly influential in subsequent game design, particularly on first-person shooters, and considered it far ahead of its time. It has been included in several "greatest games of all time" lists. In 2007, Irrational Games released a spiritual successor to the System Shock series, titled BioShock, to critical acclaim and strong sales.