• Ceda workers : Dead Center 1st & 2nd Chapters, No Mercy, The Last Stand;
  
• Clowns : Dark Carnival;
  
• Mud Men : Swamp Fever, The Last Stand;
  
• Workers : Hard Rain.

Note: You have to be the one to kill them and then pick up the Boomer vomit.

• The Guitar can spawn in other campaigns, but mostly on Dark Carnival.
  
• The Nightstick : The Parish.
  
• Machete : mostly on Swamp Fever.

Note: You need at least 2 people for this method.

Note: The effect of an Adrenaline Shot lasts 15 seconds.

Note: You can load the Mutation "Last Man on Earth" and there will be no bots to bother you, and no Common Infected.

Note: You can do this in the Versus gamemode as well.

Note: Pressing "E" on the keyboard inside the room awards you a Golden Crowbar, although it does not count towards the GOLDEN FREEMAN Achievement.

Note: Pouring a gas can adds 20 seconds.

Note: "Being chocked" means that the Smoker must have dragged a Survivor all the way up to him, where he wraps his tongue around them and starts hitting them.

• There is now friendly fire. It inflicts half damage to the Survivors.
  
• The Infected receive x0.5 damage (two shots with most weapons), while dealing 20 damage from the front, 10 from the back.
  
• The Tank has 8000 health points, incapacitates Survivors in one hit and deals 150 damage when pounding (killing an incapacitated Survivor in two hits).
  
• The Witch receives × 0.5 damage to the body, can instantly kill a Survivor regardless if they are in normal or black-and-white vision and is startled in 4 seconds.
  
• Special Infected are smarter, have more health and deal more damage.
  
• Fire inflicts 40 damage per second to the Survivors (that's a lot of damage!).

• Dead Center
  
  • Pretty straight forward. When you have to deliver the Cola's, have one friend hold the entrance of the Market while you deliver them (Infected only spawn outside).
    
    
  • At the finale, make sure to be FAST cause you don't want to be dealing with 8k health Tanks, so make sure you all know the map.
  
  
• Dark Carnival
  
  • This one is a bit harder. The first 2 Chapters are OK, just run and gun. But, when you get to "The Coaster" (3rd Chapter), it will get more difficult. Since it's a narrow tunnel most of the time, be careful to stand side by side so you won't be dealing team damage (this was the primary cause of our losses on this map). The tank may or may not spawn on the first level, but if it doesn't it will definitely spawn at the second level, right before the exit.
    
    
  • The Barns shouldn't be much of a problem until the gate, where a giant horde will spawn. You can all camp on the barns' rooftops, the ones you drop down to open the gate. Have one friend go and activate it. Few Infected spawn there, but be careful of Smokers. After you're finished with the horde, as you go through the gates, another one will spawn. Infected will also come from behind, above and every direction - so have someone look behind because one M60 is enough to hold the front. Be quick because the Saferoom is right around the corner.
    
    
  • The finale is a pain. You can have one Tank spawn right at the start of the campaign, so just die because it's not worth it. Before turning off the lights and starting the concert, stockpile and remember where the items spawned.
    As for strategy, make one up based on your skills. You can choose to stay scattered to cover more ground, but be careful to not get incapacitated. Or, you can stay together on the stage, where the most items are. It really depends on the item spawns and the way you play.
    There are 3 Tank spawns until the helicopter arrives, and 2 spawn right as it lands. So, as soon as you hear it, run for it as fast as you can, don't bother with the Tanks, just get inside the heli .
  
  
• Swamp Fever
  
  • The first three Chapters are very easy. There are tricky parts, yes, like the Witches - be careful, but just turn off the lights and don't fire (right click to stun Infected to get further away from the Witches, and then kill them)
    
    
  • As for the finale, the mounted machine gun is useless. One Tank will spawn, and then a pair of two will soon after. After the last 2 Tanks have been killed, head for the gates. Be careful! they can spawn inside the mansion. A great strategy is to have it target a player, and have that player loop around the balcony, while the others shoot at the tank. The narrow corridors will slow down the tank and it won't kill its target.
  
  
• Hard Rain
  
  • To be added.
  
  
• The Parish
  
  • To be added.

• Realism removes the outlines that normally appear around teammates when there is an obstruction between one another.
  
• Common Infected & the Witch receive × 0.5 damage to the body on Easy difficulty, × 0.37 on Normal, × 0.25 on Advanced & Expert.
  
• You do not respawn in Rescue Closets.

• Chainsaw Massacre - all players have infinite Chainsaws.
  
• Gib Fest - all players have infinite ammo M60 Machine Guns.
  
• Riding My Survivor (in Versus gamemode) - only Special Infected that spawn are Jockeys.
  
• Last Gnome on Earth - you have Gnome Chompski with you in each Saferoom.