
Įach Survivor can carry one each of five categories of equipment: primary weapons, secondary weapons, throwable weapons, major medical supplies (which also includes ammunition upgrades) and minor medical supplies.


However, the final level in each campaign requires the Survivors to call for rescue and either survive a prolonged onslaught until rescue arrives, pass through an especially challenging gauntlet of Infected to reach an escape vehicle, or (in Dead Center and The Passing) collect and utilize fuel cans to enable their escape. In every campaign, most levels involve the Survivors attempting to reach a safe zone and close the door once they are all safely inside. As in the first game, each campaign is presented in menus and loading screens as a film starring the four Survivors and features, upon completing a campaign, a faux credits screen which acts as the final scoreboard for the players and recaps certain performance statistics for the group. The game presents five new campaigns, each composed of three to five smaller levels. Like its predecessor, Left 4 Dead 2 is a first-person shooter with a heavy emphasis on cooperative gameplay.

The gameplay is procedurally altered by the " AI Director 2.0", which monitors the players' performance and adjusts the scenario to provide a dynamic challenge.

The Survivors must fight their way through five campaigns, interspersed with safe houses that act as checkpoints, with the goal of escape at each campaign's finale. Set during the aftermath of an apocalyptic pandemic, Left 4 Dead 2 focuses on four new Survivors, fighting against hordes of zombies, known as the Infected, who develop severe psychosis and act extremely aggressive. Left 4 Dead 2 builds upon cooperatively focused gameplay and Valve's proprietary Source engine, the same game engine used in the original Left 4 Dead. The sequel to Turtle Rock Studios's Left 4 Dead, it was released for Windows and Xbox 360 in November 2009, Mac OS X in October 2010, and Linux in July 2013. Left 4 Dead 2 is a 2009 multiplayer survival horror first-person shooter developed and published by Valve.
