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