The Left 4 Dead 2 mutation for owners of "The Passing" DLC for the next week is "Headshot!". In this mode, only headshots and decapitations will drop enemy zombies.

"Shoot them in the arm, shoot them in the leg, shoot them in the chest - it just doesn't matter! The only way these zombies are going down is with a head shot. Other hits will stumble them back, but only a head shot or decapitation will kill them." This mutation is available for the campaign.

Additionally, a patch has been applied to the PC version of the game via Valve's Steam digital distribution service. The Xbox 360 version will eventually see these changes implemented.

Valve describes the changes on the Left 4 Dead Blog:

While not removing Defibrillators, we have made some changes to them. We scaled dynamic Defibs based on map length. This means unless the Defib was expressly set by the level designer to have more, the Director will only spawn them on a long map. The Director will also cap the number to one per map.

Using the Defibrillator is no longer free; there is now a 25 point scoring penalty for using a Defib. That means each time you use one, you will have 25 points removed from your final score. Will your revived Survivor make it far enough to be worth it?

Health kits will also be less numerous as we have removed the Director's dynamic Pill conversion. Previously if the first team was injured, the Director would spawn First Aid Kits instead of Pills for both teams. Now the Director will always just spawn Pills.

The Jockey received some minor buffs. His damage per second was increased and we removed his damage delay.

The full patch notes can be found below:

Addon Update

• Fixed a crash when the vpk file limit was reached.
• Fixed an issue where wireframes were displayed while playing Addon Campaigns.

• Added a 25 point scoring penalty for using a Defibrillator.
• Scaled dynamic Defibrillators based on map length with a maximum of 1 per map.
• Removed dynamic Pill conversion to First Aid Kits.
• Removed Explosive Ammunition.
• Increased Jockey damage per second.
• Removed Jockey�s damage delay.