Platform: X-Box 360

Left 4 Dead (abbreviated L4D) is an upcoming multiplayer co-operative survival horror first-person shooter game by Valve Corporation. The game has been built using Valve's Source engine and will be available on Steam and the Xbox 360.

Left 4 Dead pits four human playable or AI controlled survivors of an apocalyptic pandemic against hordes of aggressive "Infected". The Survivors' goal is to help each other make it through various scenarios to safety. The Infected are controlled by an AI that dynamically balances difficulty and mood depending on the players' progress and situation. In an alternate game mode, human players can control up to four mutated Boss Infected with special abilities and cooperate to stop the Survivor players.

The expected release date for Left 4 Dead is November 18, 2008 in the United States and November 21, 2008 in Europe to coincide with the tenth anniversary of the release of Half-Life. A demo will be available in early November for Windows and Xbox 360 users.


Gameplay
Left 4 Dead is played in first-person perspective, where up to four players take control of the four main characters of the game; the "Survivors". If four human players are not available to play, the Survivors can also be AI-controlled bots. They play through the levels fighting off the Infected, which are humans who have been infected with a mysterious disease.

The game is focused on cooperation and team play; colored outlines are visible through walls to help players stick together and coordinate their movement, and Survivors can be knocked down by the Infected and only helped up by another player. If a teammate is downed after being helped up twice, without tending to his wounds in between, the player is out and must wait 60 seconds before respawning. Certain "Boss Infected" also command special attacks, such as a Hunter's pin, which requires assistance from a teammate to get out of. Survivors can also share first-aid kits and help each other heal. Left 4 Dead has full friendly fire that cannot be switched off, increasing the need for caution around other Survivors.

The Survivors communicate by automated voice commands that are accessed by quick menus, and some will also sound off automatically when doing such things as reloading or spotting Infected. Over 1000 unique lines have been recorded for each Survivor. Additional communication of player actions is conveyed through character lights. Also, weapon-mounted flashlights and muzzle flashes help the players in determining whether their companions are shooting, performing melee attacks, reloading or moving.

The game is experienced through four scenarios that take place in various urban and rural locales, such as a hospital, an airport and a murky countryside. Each scenario is divided into several shorter sections marked by safehouse checkpoints, where players can heal, re-arm, calm their nerves, save their progress and retrieve players who were killed. The levels are neither linear nor completely open-ended or free-roaming. There are a number of alternate routes to follow with more supplies and alternate objectives. At the end of each scenario, the players must defend a position from an onslaught of Infected until rescue arrives. Each scenario lasts between 45 and 75 minutes.

Versus mode
In the deathmatch Versus mode, four additional players can take control of powerful Infected with unique abilities, amongst the other AI-controlled Infected. The playable Infected numbers are limited so players must select their preferred Infected and wait for it to spawn, with the Tank as the exception, it being able to only spawn a few times in each scenario. The Infected have the ability to see Survivors through the walls at a certain range if the Survivors are running, have the flashlight on, or are talking. The Infected can also see in the dark, unlike the Survivors. Infected spawn ahead of the Survivors and can, if they stay still, see a marker for their likely path of advance so they can set up ambushes. Throughout levels, Infected-only ways up buildings are marked with symbols. These can be climbed and used for ambushes, especially with the Infected immunity to falling damage.