Full list of all 65 Left 4 Dead 2 achievements worth 1,500 gamerscore. It takes around 20-25 hours to unlock all of the achievements in the base game.
The base game contains 50 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 15 achievements worth 500 Gamerscore.
As the Charger, bowl through the entire enemy team in a single charge.
In a Versus round, leave the saferoom to defibrillate a dead teammate.
Survive all campaigns on Expert.
Collect 10 vials of Boomer vomit from infected CEDA agents you have killed.
Revive 10 dead Survivors with the defibrillator.
Kill a Tank with melee weapons.
In a Survival round, get a medal only using melee weapons.
Cross the bridge finale in less than three minutes.
Prove you are faster than Moustachio.
Survive a campaign on Expert skill with Realism mode enabled.
Revive 10 incapacitated Survivors while under the speed-boosting effects of adrenaline.
As the Charger, grab a Survivor and carry them over 80 feet.
Cause 25 gas can drops as a Special Infected.
Collect 100 gas cans in Scavenge.
Form a team and beat an enemy team in 4v4 Versus or Scavenge.
As the Spitter, hit every Survivor with a single acid patch.
As the Spitter, spit on a Survivor being choked by a Smoker.
As the Charger, grab a Survivor and smash them into the ground for a solid 15 seconds.
Make a Survivor drop a gas can during overtime.
Collect 15 gas cans in a single Scavenge round.
As the Jockey, ride a Survivor and steer them into a Spitter's acid patch.
Stop the enemy team from collecting any gas cans during a Scavenge round.
Rescue Gnome Chompski from the Carnival.
Kill 15 Infected with a single grenade launcher blast.
Navigate the impound lot and reach the cemetery safe room without tripping any alarms.
Ignite 50 Common Infected with incendiary ammo.
Prove you are stronger than Moustachio.
Honk the noses of 10 Clowns.
Kill a Charger with a melee weapon while they are charging.
Survive the Hard Rain campaign.
Navigate the sugar mill and reach the safe room without killing any Witches.
Survive the Swamp Fever campaign.
Kill 10 swampy Mudmen while they are in the water.
Defend yourself at the crashed airliner without taking damage.
Finish a campaign using only melee weapons.
Survive the Parish campaign.
Use every melee weapon to kill Common Infected.
Win a game of Scavenge.
As the Jockey, ride a Survivor for more than 12 seconds.
Use a bile bomb on a Tank.
Decapitate 200 Infected with a melee weapon.
Survive the Dark Carnival campaign.
Using a Molotov, burn a Clown leading at least 10 Common Infected.
Kill one of each Uncommon Infected.
Kill 100 Common Infected with the chainsaw.
Deploy an ammo upgrade and have your team use it.
Kill a Jockey within 2 seconds of it jumping on a Survivor.
As the Jockey, ride the Survivors twice in a single life.
Survive the Dead Center campaign.
Kill a Spitter before she is able to spit.
Survive The Passing Campaign.
Play the new Midnight Riders song on a jukebox.
Play 6 Mutations.
As the Charger, grab a Survivor and crash them through 8 chairs at the wedding.
Using the M60, kill 25 infected without letting go of the trigger.
Collect 10 items dropped by a Fallen Survivor.
Kill a Tank only with damage from the original Survivors.
Open 5 foot lockers.
Knock off the heads of 18 infected with the golf club.
Play 5 full games of Scavenge on The Port.
Complete "The Sacrifice".
As a Special Infected, incap someone who is trying to sacrifice themselves.
Kill a Special Infected with an exploding barrel.
Have all 3 generators running at once in "The Sacrifice" finale.
Have Bill sacrifice himself for the team.