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