The core gameplay consists of elements of a third-person shooter and a driving game, affording the player a large, open environment in which to move around. On foot, the player's character is capable of walking, running, swimming and jumping, as well as utilizing weapons and basic hand to hand combat. Players can steal and drive a variety of vehicles, including automobiles, boats, airplanes, helicopters and motorcycles.

The open, non-linear environment allows players to explore and choose how they wish to play the game. Although storyline missions are necessary to progress through the game and unlock certain areas and content, they are not required, as players can complete them at their own leisure. When not taking on a storyline mission, players can free-roam and create havoc (e.g. drive-by shootings, robberies, etc). However, doing so can attract unwanted and potentially fatal attention from the authorities. The more chaos caused, the stronger the response: police will handle minor infractions, whereas undercover cops, SWAT teams, the FBI, and the military respond to higher wanted levels. (Wikipedia)

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