But that's a problem for the single-player portion. That intensity, the thrill of fighting for survival alongside your pals, just disappears. When it's just you and three computer-controlled bots, you don't care. There's no reason to care about your companions. There's no communication, no intimacy. Frankly, it's boring, and with good reason.

Left 4 Dead wasn't made to be a single-player game. There's a reason we refer to it as a cooperative zombie-killing game. The action here is centered around teamwork, around cooperation. It's not a single-player shooter focused on narrative progression, scripted moments, and clever puzzles. Not even close.

I don't say this to attack the game or to fault Valve, but rather, to make sure you know what you're getting into. If you've got someone to play with, Left 4 Dead will provide some of the most memorable multiplayer experiences in a long, long time. There will be blood, there will be chaos. There will be good times, and there will many, many stories for you to look back on.

But if you're not looking for multiplayer, then quite frankly, don't bother. In that case, Left 4 Dead just isn't the game for you. - Chris Faylor

Blake's Take
No running off alone. It's a rule that's easy to learn but tough to master.

Left 4 Dead is the refinement of Valve's previous teamwork experiment, Team Fortress 2. Much of that game's thought process seemed to be centered on rewarding teamwork and occasionally punishing playing selfishly. But where TF2 has a complex, rock-paper-scissors team chemistry built on class choices, Left 4 Dead is simple and straightforward. You absolutely must play as a team.

But how many zombie movies have you seen where the whole crew sticks to the plan? Indeed, it was that temptation that broke up Team Shacknews many a time. Faylor, for one, gave into the impulse so many times that I began calling him Dora the Explorer after yet another detour turned into cries of "Hunter's got me! Help!"

For those who enjoy causing a little mayhem, the game's Versus Mode will fill the need very nicely. Four humans playing as zombies have the potential to wreak havoc on a team of four survivors much more quickly than the AI Director.

Even then, however, working with your teammates is essential. The game staggers the insertion of each zombie team player into the game by about 15 seconds, so impatient players jump right into the fight by themselves, only to be easily dispatched by four gun-touting survivors.

At that point, the game ceases to be a tense co-op thriller and becomes an even tenser competitive experience. Both teams switch between survivor and zombie play, so whichever team has better chemistry will doubtlessly win.

So, have some advice from four of us. We survived on our own, but went home with our tails between our legs after Valve out-team-played us. Don't be like Dora. No running off alone--that's a rule. - Blake Ellison

Gibson's Take
The most fun I've had playing co-op was with Diablo 2 and DOOM 2. There have been a few good games I've enjoyed among friends since then, such as Mario Party, Fusion Frenzy, Halo or NHL Hitz. But none have crossed the threshold of greatness to be placed alongside those classics.

Left 4 Dead is a co-op game, and you will stick with your buddies. The moment you wander too far away from your group, you will die. Constant communication and staying with your team is greatly rewarded, and at the highest skill levels, required. It's great.

I'm sure there is a certain degree of nostalgia that has caused me to elevate DOOM 2 to a level of co-op greatness. So taking a step back to look, I think Left 4 Dead may be the best co-op experience of my gaming life. I just hope that the intimacy of the LAN experience translates well to the internet. I'm betting it will. - Steve Gibson

Developed by Valve, Left 4 Dead is now available for PC and Xbox 360.