L4D's mid-level crescendo events and chapter-capping finales are straightforward compared to these. But alongside these brilliant moments there sit two sadly missed opportunities for creative design. Other than a stand-out crescendo event on a rollercoaster track and a tame target-shooting minigame, the Dark Carnival campaign only sparsely displays the playful circus theme I expected, while Swamp Fever reverts to the familiar finale template of 'defend this area with a machinegun turret while we wait for a rescue vehicle.'
The gas-gathering of the Dead Centre finale is so tense and satisfying that L4D2 makes an entirely new competitive multiplayer mode out of it, and it's my single favourite addition. In Scavenge mode, two teams of four compete in short alternating rounds to retrieve gas cans scattered around the map and pour them into a generator in the centre to score points and add time, while the other team plays Infected trying to stop them. Giving the survivors an objective that supersedes survival changes the dynamic and mass-produces thrilling moments.
It's not about knowing when to expect a Tank or in what closet you're most likely to find a pipe bomb, so committing map layouts to memory isn't nearly as important as it is in Versus (and by the way, all five campaigns fully support Versus). It's about on-the-fly gunwork and communication. Best of all, it puts the survivor team into difficult situations that demand split-second responses - such as whether to pour a gas can into the generator to score more points, or save a teammate in the hopes that you'll be able to get more gas with their help.
For the Infected team, Scavenge isn't necessarily about killing survivors, but rather delaying them and denying them gas cans until time runs out. The Infected can pull evil tricks to prevent survivors from scoring - for example, the Spitter's acid goo can ignite any gas canisters that have been dropped by survivors, so if the human team fails to protect can carriers or piles gas cans close together, a well-placed loogie will set them back to square one.
I can't overstate how much these enhancements will extend the life of L4D2, but gun-wise, there's nothing that gives players a genuinely new tactical option. New flavours of every gun class, such as a three-shot-burst assault rifle and a powerful magnum handgun, let you pick up a version that suits your fighting style, but there are no remote mines, no body armour or defensive items. The grenade launcher is the most novel - you can't reload it from ammo stacks, so you get a finite number of shots from a slow-reloading, powerful tube of ranged splash damage that, in the wrong hands, is a friendly fire disaster waiting to happen.
The new consumable items - explosive and incendiary ammo that lets you kill tough zombies a little faster, and an adrenaline shot that speeds you up a little - are in a similar boat: they don't profoundly alter the game, but serve more as fun condiments to what's already there. The new throwable item, Boomer bile, is a cousin to the pipe bomb that can be used to lure hordes away from your group, so it doesn't introduce many new tactics (except in Versus mode, where it can blind a player-controlled Tank). A defibrillator can now be carried in place of a health kit to revive dead comrades, which beats the heck out of fighting your way to a respawn closet short-handed.
Oddly, the new survivors didn't recreate the charm and sense of familiarity of Louis, Francis, Zoey and Bill. There's no running "I hate..." Francis gag or Zoeyisms to break the tension - I noticed fewer allusions to 'Nam or other events to give us a sense of these characters' histories. And as before the closest you'll get to exposition are the forum-style scrawls inside safe rooms, vague rants about the government, or a scripted helicopter flying overhead. But in that respect Valve didn't fix what wasn't broken.
Left 4 Dead 2 refines the game in interesting ways, but does not reinvent the Left 4 Dead experience. As before, the appeal of the kill-advance-kill mechanic will likely erode over time, but measured in moments you're left talking about, Left 4 Dead 2 is off the scale.
For another verdict read Edge's Left 4 Dead 2 review.
Gorier, chainsawier, co-opier, and more infectious. A refreshed stack of content for the best zombie game ever.