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