VS Mode
VS is by far the most difficult and complicated mode in L4D (kinda depends on how good the other team is too). Playing against zombies controlled by people who think and devise coordinated strategy's is lots of fun. It's even more fun with tips and tricks that will help you win!
Survivors
Playing as survivors is where you make all your points. The further you get with more people the higher you're score is. To kick a teams ass in versus you need to be a good survivor.
Health – Pills / Med packs
Managing your health correctly is huge in vs. Unlike campaign you do not wait to wait for black and white mode to hit. Human controlled special infected are too dangerous to take that risk, also if you make a mistake and get killed you wont respawn.
However, the lower your health is the more health you recover, and the higher your team score will be. You almost never want to heal with health that is either green or orange. When your health reaches red its time to use pills.
Always use pills before med packs. Pills are easier to find and there's a good chance you'll find more and be able to hold on to that med pack a while longer. Of course if you have no pills its time to heal up. Always let your team know that your going to heal (Do not want to get left behind in vs!). Try not to heal out in the open. Smokers and hunters target weaker lower health players. If you're healing that's you! Get your back to a wall and if possible get some over head cover to prevent high damage pounces.
Speed
Speed is every thing in vs. Going slow lessens your chance of reaching the safe room. Why is that? The infected players are working with a spawn timer. Every time you kill them they have a set amount of time before they can respawn. So the faster you move the less spawns they get and the less chances they have to do damage.
There are some limits to speed though. You do not want to move so fast that you get mobbed by common infected, this makes you an easy target. Moving too fast is also a good way to get split up. We do not want one guy making it to the safe room and leaving every one else out to dry, or have the guy who runs ahead get killed on their own.
You do not want to be a fast player. You want to be a fast team! Good voice communication is the best way to achieve this. It's pretty much impossible to type and move fast at the same time.
Pipe bombs
Speed is key. Pipe bombs are great because they can help you maintain speed. Unlike campaign mode you do not get to hold onto equipment from previous maps. You do not want to waste useful items like pipe bombs by getting to the safe room with them still in your inventory.
Like I said before the best way to use a pipe is for maintaining speed. The most common slow down is a multi hit boomer vomit. If two or more players get vomited on then you have a good reason to part with your pipe. If only one player has been hit try to save it. Its pretty easy to help out one guy who's been gacked on.
Overcrowded rooms are another good spot to use bombs. If you can not cut down a path in under 10 seconds its justifiable to use to use your pipe. Same thing with random hordes. If you're going to use a pipe on the horde make sure you do it early. There's no point fighting half of them off then deciding to throw the pipe. If your in an easily defensible spot I would recommend holding onto it.
Molotovs
I always take molotovs over pipe bombs in contrary. Pipe bombs only take care of common infected which most of the time are just a nuisance. Molotovs are good for handling the big guy. A player controlled tank is the most dangerous opponent in Left 4 Dead. But even the best tanks still burn.
Molo's can also be used to burn down other infected. Although you want to be careful throwing one near a hunter. Burning hunters do double damage. Every other class of infected slowly burns until their health runs out. I do not recommend using molotovs like this without you have tons of them or have no choice. They do not attract infected so you can only kill them in one small area.
Infected
It's recommended that you play campaign mode before jumping into a versus game. No amount of campaign will get you ready to play infected. But that's okay because I have you taken care of my friend. I'll sort out how to be an effective infected player.
Teamwork
Teamwork teamwork teamwork. Did you catch that? Why wont I shut up about team work you say? I'll tell you why! Because you are not beating any survivors without it! If you've ever won a game of versus you have used team work, even if it was an accident.
Infected are weak on their own. Filtering in weak infected one at a time is incredibly easy to beat. Many players lack patience, do not be that player. They immediately spawn in as soon as their timer is up and throw them selves at the enemy. They do not care what the survivors or their own team are doing they just want to jump into the action.
And 90% of the time those players get their shit owned. Usually they end up with the most deaths and low score. No class of infected can stand up to a good survivor team by its self, even the tank needs a little help.
Support the tank
Like I said before every body needs some help, even the tank. Even a good tank player can get killed doing little or no damage to survivors. If the tank is going to do any serious damage you have to even up the odds a little. His rage meter is longer than 30 seconds, so you can afford to wait for most or all of you're team to spawn in.
If you're really luck you might even get to play 5 vs 4. When the tank first shows up some one is going to be told they are becoming it. If you are spawned in and get this message the computer will take over your common infected while you get to play as the tank. So if every one else gets spawned in you will have 5 special infected in play.
By far the most important infected for supporting a tank is the boomer. Getting a good boom off can almost guarantee a win. The boomers prime target should be any player with a molotov. Checking the score board will tell you if the enemy players have molotovs or pipe bombs. Normal player with molos will move to the front when a tank comes and hold it out. The perfect target for a boomer. If you can get that guy occupied with your minions the others should be tank food.
Hunters / Smokers are also important supporters. Any one with a molotov is some one you want to pounce / pull first. A good strategy is to pounce a guy out front. Then have a boomer pop out and vomit on the front runner and any one who comes to help him while a smoker pulls one of the none boomed residents away, the tank cleaning up any thing left behind.
This means play as the tank takes patience. Do not just charge in because you have 5,000 health. It goes down quickly between molotovs and focus fire. Taking the extra seconds to wait for team mates makes such a huge difference in tank effectiveness.
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