Version tested: Xbox 360
Microsoft loves exclusives, but in Left 4 Dead's case it's really breaking new ground: If you want to play Crash Course on the PC, don't wait for me to convince you, just go ahead - it's free! If you want to play it on Xbox 360, you might want to hang back, because it's 560 Microsoft Points (£4.76 / €6.72). Apparently this is nothing to do with Valve, the people who made the content - it's because Microsoft doesn't want all the other premium DLC getting upset about being shown up. The fact we had to haul that explanation out of Valve suggests even the money men in Redmond find it a bit shameful.
They can at least drown their sorrows in the blood of a thousand zombies, because Crash Course is an intense little campaign that really kicks you around the houses for the half-hour it takes you to stagger through its two chapters. With the original four Left 4 Dead campaigns clocking in at around an hour each for a straight play-through, Versus games were lasting around twice that, so the idea here is to give the competitive side of the game's dedicated fans something that's just as demanding but over a shorter distance.
It also bridges a narrative gap - between climbing into the chopper atop Mercy Hospital in the first campaign and crawling onto a highway at the start of the second, Death Toll. We don't learn much more about what's going on in the world during Crash Course, but we do get some more quips from the crew (Zoey points out that climbing into a helicopter with a zombie pilot is poor survival logic), and judging by the writing scrawled on the wall of the midway safehouse we also discover that Valve thinks someone called Alison is a bit of a numpty.
With carte blanche to fill the intervening period, it's perhaps a little disappointing to start off by running around the same dark alleys and warehouse interiors that we've raced through dozens of times before. Articulated lorries and wire-mesh fences funnel you through buildings and across a few streets before you drop down to a riverside and circle up to a bridge; then following a crescendo moment involving a Howitzer you cross the water, do a safehouse transition and fight your way to a truck depot where you need to power up a generator while fighting off the horde for a finale. (The Howitzer and generator bits form the basis of two new Survival mode sections.)
That initial disappointment seeps away though as you start to appreciate the devilish way Valve leads you into unavoidable traps and how even seemingly incidental touches - like shrubbery covering the approach to a raised highway - are calculated to make you work harder for survival. The area surrounding the Howitzer crescendo is particularly well appointed - having dropped down onto a road by a river, my first group of survivors was quickly assaulted by the horde, and my attempt to avoid them by standing on a car was upset somewhat when a Tank popped up and grabbed the vantage point out from under me. The AI director is on his usual form, too, barely touching us the next time we dropped down - although he did throw in a Witch.
It's a strong finale, too. The generator needs to be started and then restarted mid-siege, but it's on the ground, which is easily assaulted from every direction. The generator powers a lift inside a warehouse that holds your ticket out of Crash Course - a reinforced truck, which it lowers in agonising slow-motion - but even if you spend the bare minimum of time outside and use an internal stairway to reach a low roof, you can rely on infected assaulting you through the double doors behind you and climbing up on three sides as well. Hunters and Smokers can also pick you off quite happily from surrounding rooftops.
There are more weapon and ammo drops in Crash Course than usual, but you can understand why, because it's a proper day out for the special infected, who can spawn delightfully close to the survivors thanks to cover from abandoned cars and lorries, and are rarely more than a few metres from their targets if they want to enter the fray from the safety of a rooftop. The patch that preceded Crash Course also introduced new HUD elements for the special infected - cooldown icons that show you which of your team-mates' abilities are available and which are recharging. Particularly useful if you're, say, a Smoker hoping to grab onto a Boomer's bile-covered victim and want to check whether the big man has a gob ready to go.
There's an Achievement for hauling in a bile-covered survivor, along with another for incapacitating three survivors as a team within five seconds of each other, and some lower-hanging fruit like restarting the generator within 30 seconds of it going off during the finale. You can certainly obtain a good chunk of the extra 250 gamerpoints if you're playing on Xbox 360 without having to grind or pray, but some will evidently take more time and effort - like the one for killing 5359 zombies on Crash Course alone, reminiscent of the ludicrous Zombie Genocidest offering in the main game.
How well Crash Course operates for truly hardcore Versus mode fans is something it would be stretching credibility for me to address: I've played plenty of Versus, but having been in a semi-decent Counter-Strike league a long time ago I know that things are very different when it gets serious, especially this long after release. Still, you sense those people will need no convincing anyway, and many of them will be playing on the free PC version too, where critical commentary would be as meaningless as a mouse without built-in sensitivity adjustments.
For the rest of you - people who loved Left 4 Dead on either format - Crash Course is another strong, if understated slab of zombie-smashing from the people who wouldn't be told that a four-player FPS that lasts four hours was commercial suicide. In 24 hours I've already gone through it nearly a dozen times in various modes on Xbox 360, and I don't regret parting with five quid for the privilege (in fact, it was mis-priced at 800 MSP when I bought it, and I don't regret that either). Those on an extremely tight budget might want to put those pennies towards the fantastic Left 4 Dead 2 instead, but if you have a hankering now then you'll find Crash Course grows on you. Gob you later.
8 / 10
Left 4 Dead: Crash Course is free on PC and costs 560 Microsoft Points on Xbox 360.