Call of Duty: Modern Warfare 3 is a first-person shooter video game and the direct sequel to the previous installment in the series, Call of Duty: Modern Warfare 2. In its single-player campaign, players continue their struggle against an invasion by Russian Federation forces following a terrorist attack on Moscow that was framed on an undercover U.S. agent. Players can experience classic multi-character control as well as deep multiplayer support with two-player co-op Survival mode, new Kill Streak categories, and customizable strike packages for more player combat options and strategies.