Left 4 Dead achievements

Earn a Gold medal in Survival mode on any official level.

Kill all four Survivors in one life while playing as a Tank.

Finish a campaign without ever being healed.

Single-handedly kill a Tank.

Earn a Silver medal in Survival mode on any official level.

Cover four Survivors with Boomer bile at once.

Dole out 5000 total Survivor damage as a Special Infected.

As an Infected, incap a Survivor who has entered and left a safe room.

Complete one round of Survival on The Last Stand.

Kill a Witch with a single headshot.

Survive an entire campaign using only pistols.

Restart the generator within 30 seconds of it shutting off in the Crash Course campaign.