You’ve got to hand it to Valve. It’s probably the only developer on the planet that could have made Left 4 Dead. On paper the game reads like some kind of half-baked, harebrained Half-Life 2 mod. The kind of bedroom project that would never ‘make it’ because it only has four onehour missions each with plotless stories flimsily based around a gaggle of hackneyed Seventies zombie movies.

‘Let’s get this straight. You shoot your way through a bunch of nondescript zombies, relying entirely on AI and the odd scripted event?’

‘Yeah, and all of the character’s attributes are identical and you’ve only got a few weapons, a Molotov and a pipe bomb to play with.’

‘Right. Er, thanks for the pitch. Close the door on your way out.’

‘Wait… did we mention we’re using a four-year-old engine to make it?’

‘[click] Security to the board room…’

The simple fact is, at any other dev house with anybody else’s money Left 4 Dead wouldn’t have made it off the drawing board. At Valve, however, these kinds of ideas aren’t just born, they’re incubated, pampered, burped and in time they grow into solid granite monoliths of modern games design. We could waste hours mulling whether it’s pure vision, the simplicity of the Source engine or the backing of largest digital download service on the planet that allows them to take these kinds of design risks and get away with it, but the net result is that Left 4 Dead doesn’t just work, it redefines the online FPS.

Its less-is-more approach is actually quite a refreshing break from the recent trend in firstperson shooters too. There’s no 30-hour convoluted quest to contend with, no weapon degradation, no topographic map reading and certainly no fourlegged friend to try and keep alive – it’s run-and-gun all the way, with the odd pant-changing pit stop thrown in to keep your nerves from burning out. It’s the kind of fast-paced quick-fix action that puts us in mind of the past masters like Doom and Serious Sam. There is wave after wave of undead enemies between you and the next classic zombie apocalypse scenario, and all you’ve got is a health pack strapped to your back and three other people to keep you alive. While the inclusion of co-op multiplayer really makes this game work, it’s actually the nature of the AI that keeps you coming back for more.

While it would have been easy to have scripted the zombies to catch you and your online compadres at various bottlenecks during your escape, Valve’s AI Director ensures no two play-throughs are ever the same by constantly monitoring your progress and dealing you just the right number of enemies at just the right time to keep you on the brink of despair. One pass through the hospital lobby might go painlessly enough, yet the next zombies will drop down through holes in the ceiling, climb through windows and beat down doors until you’re surrounded by utter chaos. The inclusion of four uber-undead ‘boss’ enemies also throws in a certain level of unpredictability. These guys can wreak serious havoc by vomiting zombieattracting bile, wrapping their 50-foot tongues around your neck, pouncing from great distances or – worst of all – throwing a car at your head or punching you 20 feet off the top of a high building.

We found ourselves moving gingerly through an abandoned and boarded-up township actually whispering the all clear over the built-in voice chat as we pressed on toward the safe-room. You make allies quickly when you’re online in L4D, because without them you’re toast.

… continued