Zombies seem to be the flavour of the season. Rockstar might have tickled your fancy with GTA4’s recent infestation and Treyarch may have raised a smile with their context crushing arcade massacre granted upon completion of Call Of Duty World At War, but if you are still craving some real undead mayhem in your life then Left 4 Dead will scratch that itch with no remorse.

Left 4 Dead has a simple premise; you are part of a team of four survivors fighting through waves of infected during a zombie apocalypse. Running on Valve’s Source engine, you would be forgiven for quickly writing this title off as an overpriced Counterstrike mod with zombies - thankfully that isn’t the case. Instead, Valve have developed an impressively unique and nerve wracking survival horror shooter.

The main game itself is split into four distinct campaigns each consisting of five chapters. Whilst progression through each campaign is undeniably linear, the events that unfold throughout your travels are rarely scripted. Each campaign tends to have a set piece bookending each chapter and one magnificent crescendo of mayhem as the survivors near rescue. However, rather than a pre-planned sequence of events in the vein of Gears of War or Call of Duty 4, here Valve have simply made the trigger for an event transparent to you giving your team time to prepare for a particularly nasty onslaught of undead civilians.

Aside from these few sections the whole experience is otherwise totally organic. The games pace and challenge is controlled by the seemingly sadistic AI director that decides where and when the next zombie horde will appear. Rather than simply randomising the attacks however, Valve have designed a system perfectly tuned to keep you on your toes and induce a never ending sense of dread and panic . Only on multiple playthroughs will you begin to genuinely appreciate the completely unpredictable and merciless dealings of Left 4 Dead.

It’s not just run-of-the-mill zombies that fancy a nibble though; there are five special classes of the infected also vying for a taste of your precious ammunition. The Hunters are the friskiest of the bunch and will pounce on you pinning you to the ground. Smokers work from a distance using their un-naturally strong and adhesive tongues to drag you away like some sort of psychotic Frogger and Boomers will spray you with their own special brand of vomit that draws the zombie horde straight to their victim. The most hazardous couple though are the Tank, effectively a damage dealing bullet sponge, and the Witch who will harmlessly sit alone, crying, until someone startles her which will launch her into a perilous frenzy.

The translation of Valve’s previous games to console has generally been less than successful but Left 4 Dead feels closer to playing with a mouse and keyboard than any PC-console shooter before it. The controls are tight and responsive and even the right bumper has had a 180 degree turn dedicated to it (something which other shooters should take note of). The weapons are all balanced and tuned to ensure there won’t be any clear superiors and each one feels suitably devastating as they tear apart zombie flesh, painting the environments in real time blood.

Whilst there is no apparent overarching plot to Left 4 Dead, Valve have still managed to utilise their well known talent for telling stories through environments by instilling a subtle narrative throughout which you need only glance at the ramblings on a safe-room wall to begin to notice. Each campaign uses to the same party of four characters from which you can choose one to inhabit. Whilst essentially acting as blank avatars with no individual skills, there is still a rather charming amount of character to all of them. The manual provides a completely unnecessary background and motivation for them all that is followed through on through various quips and attitudes in the game. This certainly helps create a sense of being part of a team when playing solo, however you’re not getting even half of the experience that way. . .

This game was clearly designed to be played with teams of people online and that’s where Left 4 Dead really marks its territory. Success in each campaign will depend entirely on the team sticking together and pooling their health resources to help each other through. If you intend on keeping any health you pick up solely to yourself then you really are not going to be a very desirable partner. The AI of your team-mates is still relatively competent, but nothing really compares to sharing a true moment of panic with three other people holed up in a room next to you.

Finally, there is the rather experimental Versus mode. This allows up to two teams of four players facing off against each other. Sounds fairly typical, but here’s the curveball - one team plays the side of the infected! The human side have the same objective as in the campaign and must fight their way to a designated extraction location for survival. The other team of players get to assist the zombie horde by playing as one of the four special zombies (the witch isn’t available here). Each of the Hunter, Boomer, Smoker and Tank’s respective skills are available to their players and your task here to is to hunt and halt the survivors and prevent them from reaching rescue. The learning curve for playing as zombies is intimidatingly steep and the speed at which you’ll be taken down can be disheartening to the impatient. Once you get used to the pace of play and tactics required however, it becomes obvious how well balanced and iterated to perfection Versus is.

Unfortunately, it’s unlikely that 360 owners will enjoy the inevitable array of free content that PC users will be treated to, so the lifespan of Left 4 Dead will depend on the community it attracts. Valve’s Source engine may be beginning to show it’s age but Left 4 Dead proves it can still deliver the goods. I can’t recommend this title to gamers who don’t have access to Live or shy away from playing with others, but if you’re the sort that skips straight to the multi-player offerings of a new game upon release then this is most certainly for you.