Of course, developers program their titles to carry out specific functions and act in certain ways  – after a brief time in most games, enemies, worlds and even the entire experience itself can be easily telegraphed. When you boil it down, the entire game industry is based on one thing: risk vs. reward – and what’s the risk if you know exactly what steps your enemy will take?

Enter Left 4 Dead – Valve’s much touted, zombie frag-fest. Each experience of Left 4 Dead is different, from the location of enemies and weapons right down to the mood music and effect, and it’s all thanks to a sadistic bastard named "the director." Though not a character per-se, the director system plays as much an integral part in the Left 4 Dead experience as the four survivors or zombies themselves.

Think of this director system as someone constantly monitoring your progress throughout the game. Having an amazing night and offing inflicted after inflicted? The director senses that and sends a wave of enemies rushing your way. Having trouble getting through a tight spot? After a few failed attempts, you’ll see a substantial decrease in the amount of zombies coming your way. The same system applies to item and boss locations and promises to keep gamers on their toes even after multiple play throughs..

"...the director is a great way to ensure everyone has a unique experience"

While the director is a great way to ensure everyone has a unique experience, it also ramps up the game’s pace and mood incredibly. I don’t know about you, but if I was in the middle of the zombie apocalypse, and I was able to tell you exactly where the undead were, it wouldn’t be that frightening. L4D and its director system will have you thankful for your flashlight, checking around every corner and sitting on the edge of your seat. What’s more, Valve has done an incredible job keeping you on your toes even when you don’t see enemies – you’ll be listening for audio cues, like the sounds of enemies in the distance and the very creepy piano music that signifies something is about to go down.

That’s not to say that there are absolutely no scripted elements in L4D. In fact, some of the coolest moments in the game are the completely scripted Crescendo events. Trading predictability for difficulty, these events require you to call attention to yourself and attracting an incredible amount of zombies to your location. Please don’t take that lightly, these events bring a literal sea of zombies to you and your three teammates. While it can be quite overwhelming, planning for these events, and the feeling you get once you reach the end is as satisfying as any moment in games you’ve experienced in quite some time.

When it boils down to it, L4D is a first person shooter, and should be judged as so. Luckily, Valve made sure that the core elements of the genre are intact. Controls are tight and responsive, and the weapons are all fun to use. Console gamers who have been conditioned to use both triggers will be a bit thrown off when they find that the left trigger is used to pistol whip or push enemies away, but will feel right at home after awhile.

Many games give you the option to work co-operatively with your teammates but L4D simply demands it. You play as one of four survivors, who all control and play the same, but act differently personality wise. Unlike other multiplayer experiences where each player can split up, and still achieve their goals, you’ll need to stick close with your teammates if you want any hope of achieving your one goal – survival. You and the other three survivors will watch each other’s backs, heal each other and exchange items (pain killers, ammo). You’ll need to listen to the survivor’s chatter, and watch their actions, as they’ll warn you of dangers they see ahead. Each different type of enemy requires a specific type of action – for instance, don’t get too close to a boomer or you’ll get his bile, which attracts a swarm of the zombie horde all over you.  When your teammates do get into trouble, it’s your job to bail them out - -whether that means freeing them from the grasp of a zombie tongue that seems to dart out from no-where or simply keeping zombies at bay while another team member revives them. L4D doesn’t recommend you and your teammates work together – it requires it.

As fun as L4D is, it’s even better when your fellow survivors are controlled by actual humans. The game seemingly takes on a new level when you’re creeping through areas like hospital corridors, subway stations, even rural farms listening to and planning with other players. While L4D does feature fairly competent AI teammates, there still are hiccups in their performance from time to time - -you’d think the Vietnam Vet would be used to backing away from active bombs at this point.

"Playing as the infected almost feels like playing an entirely different game..."

While many games have you facing off with the undead, L4D goes a step beyond and gives players the chance to play as them. Versus mode pits up four survivors against four of the game’s higher class undead (smokers, hunters, boomers and tanks). While the survivors earn points by progressing through missions much like the campaign, the zombies, or infected as they’re referred to have one goal - cause as much damage and pain to the survivors as possible. Playing as the infected comes with quite the learning curve, the hunter’s are quicker but don’t take as much damage as the tank, while the boomers be slow and quite fragile, but they act almost as kamikaze zombies, using their bile to attract hordes of the undead. Playing as the infected almost feels like playing an entirely different game than playing as the survivors. More often than not, when you play as the survivors you have little to no time to stop and think – it’s shoot and move, shoot and move – not so when you’re on the other side of the apocalypse. As a member of the infected, you’ll be slowing the action down, finding the best paths to ambush your enemies. There are walls that can be climbed (or knocked over in the case of boomers and tanks), and dark corners to hide behind, creating brand new paths and opening up levels even more.

Though L4D’s four different campaigns (each including five different levels) can be completed in under 3 hours, the director will ensure that you won’t be getting bored anytime soon. Valve nails the b-movie zombie feel perfectly with a mix of impressive visuals (great animations make up for the seemingly dated visuals), eerie music and frantic gameplay. Left 4 Dead should be played by anyone who appreciates a good horror experience or a quality shooter.