Valve Left 4 Dead review

Left 4 Dead is an exercise in bloody carnage.

Set in the midst of a zombie armageddon, this first-person shooter pits four human Survivors against the Infected undead hordes. The former must fight their way to safety through a ravaged city, zombie-infested woods, desolate villages and the burning ruins of an airport.

In single-player mode you battle through the scenarios with three computer-controlled allies. This is great for some quick target practice, but the meat of the game is in online play. Cooperation is essential: you must heal other Survivors, warn them of incoming threats and maintain a balance between the weapons.

Each campaign is made up of several self-contained areas, which you play one after another. There's real tension, and plenty of adrenaline-pounding action, as waves of the Infected surge towards your fragile group of Survivors. These are 28 Days Later-style zombies, both fast and relentless. The standard Infected can be overwhelming en masse, but in small numbers they're easy to take down. The special Infected classes are a different story. Hunters move fast, leap and pin you down. Boomers are obese, bile-puking blobs that attract the horde if they explode or vomit over you. Most terrifying is the Witch, a pale, crying girl who launches a brutal attack on Survivors who disturb her with unexpected light or noise.

In the brilliant online Versus mode, four more players control the Infected. Even with their special abilities, though, it's a challenge to win as the zombie team. You can play organised campaigns with friends and teammates. The game balance is excellent, thanks to the Director AI system which spawns Infected in different places and quantities depending on your health and equipment.

Left 4 Dead's cooperative gameplay is great, especially if you just want some fast, gory action, but it can become repetitive due to the limited number of campaigns.