This is a little trick that some people barely know,but it's easy to master.If you become a boomer stay on top of the enemy and if they are firing at you if you fall quickly enough your boomer can absorb some of the damage from the survivors and you can just boom on them or blow up on them if your health is really low.

No mercy-On the rooftop in the beggnning go backwards jump up on the ledge look donw and you should see a vent jump down onto the vent.

On the third level of no mercy were you go out the door and into the little restraunt place go out that door head straight and when you see the first truck head down the little path to the left of the first truck and look the way closest to the wall and you should see a big metal door meele it for about a minute and it should break so you just skipped the whole gas station part

The jessus room the finale when you get outside of the place get down onto the helipad and jump onto the roof that is closse to the little stairway on the helipad climb the ladder and jump on the edge facing the right and jump on that ledge make little steps and make sure zombies can see you get close enough so that you can see the door and let the zombies break the door kill the zombies answer the radio and run into the door that the zombies broke and nothing will be able to find you.

Apparently you can kill a tank quicker if you melee him in the back/spine because it does more damage than shooting.

This only works on Death Toll, or whichever finale ends with a boat rescuing the Survivors. Have the person with the most health (only becuase they can run the fastest) wait in the farmhouse. There's a rock to the left of the house (if your facing the front) in the water. If you can jump on it, only three things can get you, Hunters, Smokers and Boomer. When you get on the rock, turn off all your lights and don't shoot anything besides Hunters, Smokers, or Boomers the invisible wall will break, and if a Boomer pukes on you, the zombies can get up, too.

The easytest way is to keep your light of at all times (but not the dark)and to be as steathy as you can as in ducking and use the pistol if few enemys and try to get head shots as much as you can and don't go all rambo all by your self and try to stick together if you go to far you will most likely to be killed by a hunter or smoker and some times a tank hopefuly this help a little

When you are in a safe room and hear a boomer run out (not too far) and get puked
On (make sure that you are in the target safe room at the end of the level) and run back into the safe room and wait for the zombies to try to get in and while being blinded by boomer puke take out your main weapon and start killing them like
Crazy. Happy hunting- Zombie Killa- Gamertag Elaumous

If you are going to use the shortcut in no mercy part one than make sure you do it
Right, because if you don't you are going to die. You will lose some health for sure when you land on the vents, so bring a health pack. Run up to the ledge and at the very end of the ledge jump. Hope you land on the vent, and wait there until
Your friends come out of the house. If you want to have some fun pull out your pistol and start picking of the zombies. Have Fun- Zombie Killa

When You are in the safe room wait for the music that signals to you that the horde is coming and then close the door. The horde will try to break in but can't so they keep standing there. Take out your hunting rifle, shotgun, Assault Rifle, or Auto Shotgun and stand their blowing there heads off! Have fun killing zombies.

Okay, before I talk, just know this only works on expert mode, okay? Ok my cousin sami was playing with a friend of his on expert mode. They get into this one safe house. They thought they were safe for the moment when a tank rips the metal door off the hinges and throws it at them, thus, killing them all. So be careful next time okay? Later.
Theplayerking.

Play this on either normal easy or advanced woudnt recomend expert do No mercy campaingn since you can skip the first part easily and it has the shorteset levels.I would pick up a heathe pack because if you get damaged enough and somebody tries to heal you you can just pull the first aid kit out and they should stop.Pain killers are important thosse are something to have it woundt count as healing.

in the BOATHOUSE FINALY if you hide in the closet to the right whenyou go threw the front door no zombies not even the tank will find you NOTE: CROUCH AND TURN OFF LIGHTS IN THE BACK OF THE CLOSET FARTHIST AWAY FROM THE DOOR

On the the level with the elevator in the No Mercy campaign. 1 person should go do this while the others keep the survivors distracted. Get to where the top of the elevator is, and keep going according to the path until you see a forklift. This glitch is a great backup if for some reason your glitch to block-off the elevator door didn't work out well. Simply move the forklift to the left, followed by pushing it forward till it is placed perfectly between the boxes and the support column of the building. IF done right, they should not be able to continue from this point.

For the 360, there is a very simple way to make sure you win on the level where you have to call the elevator on No Mercy. At the beginning of the match, make sure you are either a Hunter or smoker, (die quickly if your a boomer) and then go through the hospital until you reach the top of the elevator where the survivors exit. Looking from the door of the elevator, you should see a yellow thing attached to a small black cord. Get behind it, and start pushing it by clawing and moving it with your body. Make sure to get a good balance between pushing left and right so that you can push it in front of the elevator door. Put it as close to the door as you possibly can. If done right, when the door opens for the survivors at the top floor, they well be mad as hell, as all you have to do is slowly peck off their life with boomers, hunters, and smokers. :)

IMPORTANT NOTICE: Only 1 person should work on the glitch, the other 3 are needed to keep the survivors occupied.

For the 360, there is a very simple way to make sure you win on the level where you have to call the elevator on No Mercy. At the beginning of the match, make sure you are either a Hunter or smoker, (die quickly if your a boomer) and then go through the hospital until you reach the top of the elevator where the survivors exit. Looking from the door of the elevator, you should see a yellow thing attached to a small black cord. Get behind it, and start pushing it by clawing and moving it with your body. Make sure to get a good balance between pushing left and right so that you can push it in front of the elevator door. Put it as close to the door as you possibly can. If done right, when the door opens for the survivors at the top floor, they well be mad as hell, as all you have to do is slowly peck off their life with boomers, hunters, and smokers. :)

IMPORTANT NOTICE: Only 1 person should work on the glitch, the other 3 are needed to keep the survivors occupied.

Ok this is for offline play. First, make sure you are in a open area and you know that theres a Tank coming. Secondly, make sure you have a moltov. Thirdly, just before you fight him, change the diffilculty to expert, kill the bots on your team, then change back to easy. As The Tank first runs towards you, throw the moltov to ignite him and run like hell. The moltov can do amazing damage to a Tank over time, so keep him on fire for around 30 seconds and you will find he will die after just a few shots.

First of all, create some distance between you and The Hunter, roughly two car lengths. While hes in mid-air, about 3/4's of the way there press L and you should get perfect timing on The Hunter.

Theres a simple way to do this. Get an auto-shotgun (it will only work with this) and creep up behind The Witch and wait for her to start to scream. When she stands up, aim at the bottom of her hairline just above the neck and..... Bam! You have your achievment.

When your running aroung shooting whats in your path, if you find a corner, run to it and face outwards. This way you know that none are going to pop up behind you. This also enables you to get a good veiw of where the horde are and what direction they're coming from.

I reacommend that you play the No Mercy campain on easy, as it is the shortest set of levels in the game. Also do this in an offline campain with the bots. When moving through the campain keep you ears peeled. If you hear a boomer do one of two things.

1. Stop and look around carefully with your crew. Their inisuial reflexes will tell them to either shoot from a distance or shove the boomer and get a clean kill. (they can do this very easy) Make sure you check rooftops, halls and allyways or anywhere else the infected naturally spawn.

2. If your close to a saferoom and you hear a boomer, haul ass straight to the saferoom and kill whatevers in your way.

If you do attempt this on the No Mercy campain here are my recommendations for the finalie. Go to the top of the roof where the mounted gun is. The Boomers will usually climb the ladders to try to get you. Whatever you: DO NOT shoot him first site!! Instead shove him straight of the roof and down the ladder. If he's at the base of the ladder, still don't shoot him. If there aren't any infected around, jump off the roof, shove him then blam him. Now hoping you still have one, when the chopper arrives sprint to the helipad, face back at the helicopter ramp, and throw your molitov. This will kill any Boomer that tries to get to you, and will ignite any commen infected, hunters, tanks. Ect.

Hope this helps!

If a teammate does not co-operate with the rest of the team for no reason, here is what you should do:

1: Ask the teammate why he is not helping

2:Ask him what it will take to get him to help

3: If his terms are reasonable, he is worth playing with and you should agree to them, ( things like "Give me a health pack cause imma die" is considered reasonable) if what he says is totally out of line ( like " Because you are all f***ing morons that can't play this game for ****") then it is best to simply ask for your teammates to boot the player. Amen to booting. :p

Now it really seems like common seance, but a lot of people don't seem to understand that it is extremely important to work together toward your gole, whether it be surviving the zombies, or just completely owning the survivors. Valve created this game around the core of it to really induce teamwork, this means, that if you or somebody else goes off alone without a word, there is a 90% chance that you or that person will be vomited on/pinned down/ constricted by a special zombie. Do NOT think just because you already cleared an area, that no zombies will appear. Also, you have to take some risk and be willing to help a fellow teammate, if you have a player on your team that the rest of your teammates thinks is better than you, then it is almost always best to support the best player to get through alive. Take one for the team, basically. So don't be afriad to give away your health pack or pain pills for a greater cause. I assure you that you will be repayed in many thank yous and life savors.