Left4Dead Hands-on Preview

Games Master

The AI director is one of the most powerful and clever tools that Left4Dead has available to it. It’s revolutionary, quietly capable and surprisingly effective once you’ve seen how it really works by playing a level more than once.

But what is the AI director?

Simply put, it’s a games master – a part of the game that sits in the background and constantly monitors a hundred different settings and variables to try and deliver the best game experience to the player.

It is the AI director which is constantly watching you and once you’ve been made aware of its presence it will make you feel vulnerable and scared even when you’re in a safe house – sorry!

The AI director doesn’t just watch though, it also controls everything around you, manipulating the variables to try and deliver to you a unique game experience every time.


By constantly keeping an eye on the health and ammo of every player and then watching the time you’ve played the game for and the pace at which you are progressing, the AI director can learn where and when to spring traps on you…and when to let you slip through unmolested.

During our hands-on we got a chance to see this in action several times. There was one part of a level in particular, just before the warehouse we mentioned in the opening. It was on high ground, with a train yard below us and the edge shielded by a chain link fence and a porta-cabin over on the left. The path led along the edge, through some trees, to an air vent that let us into a safe house.

The first time I played the game I was with three journalists I didn’t know. We approached this area after battling a few smaller skirmishes, but we were all on full health and everyone had begun to naturally spread out. I searched the cabin for health and ammo, two others went to check the edge and peer over it and the last player ran straight off along the path. Then all hell broke loose.

Zombies started swarming from all directions. They clambered up the cliff, vaulted the fence and started flocking towards the two nearest survivors, who backed away while shooting – completely unaware that they were backing in to an even larger crowd that was quickly closing in.


I tried to cover them from the cabin, but grunts started pouring in through the windows and door. My shotgun couldn’t keep up a stream of lead long enough to hold them off and I went down quickly, listening to the screams of my team mates – none of whom lived long enough to revive me.

The next time I came back to play this level it was with a different group of players, some of whom I vaguely recognised. We played with radically different tactics, shouting directions back and forth and staying very close together. The smaller skirmishes were much easier. When we reached that area for the second time, we still stayed close together and collectively moved to the cabin. There we restocked, healed and waited for a few minutes for what we expected to be a massive battle. It never came.

Instead, the AI director must have noticed our higher health, different weapons and improved tactics because when we came out there was no sign of the horde. Instead we managed to get a couple of feet away from the cabin before a single Boomer cam lumbering up behind us. It was a clever move from the AI director – these guys deal in area attacks and will explode when shot, so with us clustered together it stood an excellent chance of wounding us all.

And I’m just going to end this example there because, like the other story before hand, this one ended with me killing my team mates with a Molotov cocktail. Those things really are very unpredictable!