Full list of all 101 Left 4 Dead 2 achievements. It takes around 80-100 hours to unlock all of the achievements in the base game on Windows.
The base game contains 52 achievements, and there are 7 DLC packs containing 49 achievements.
Collect 100 gas cans in Scavenge.
Form a team and beat an enemy team in 4v4 Versus or Scavenge.
Survive all campaigns on Expert.
Cause 25 gas can drops as a Special Infected.
Revive 10 dead Survivors with the defibrillator.
Revive 10 incapacitated Survivors while under the speed-boosting effects of adrenaline.
Make a Survivor drop a gas can during overtime.
Kill a Tank with melee weapons.
In a Survival round, get a medal only using melee weapons.
Defend yourself at the crashed airliner without taking damage.
Cross the bridge finale in less than three minutes.
Prove you are stronger than Moustachio.
Navigate the sugar mill and reach the safe room without killing any Witches.
Rescue Gnome Chompski from the Carnival.
Prove you are faster than Moustachio.
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.
Navigate the impound lot and reach the cemetery safe room without tripping any alarms.
In a Versus round, leave the saferoom to defibrillate a dead teammate.
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.
Survive a campaign on Expert skill with Realism mode enabled.
Kill a Charger with a melee weapon while they are charging.
Honk the noses of 10 Clowns.
Using a Molotov, burn a Clown leading at least 10 Common Infected.
As the Charger, grab a Survivor and carry them over 80 feet.
As the Charger, bowl through the entire enemy team in a single charge.
As the Charger, grab a Survivor and smash them into the ground for a solid 15 seconds.
As the Jockey, ride a Survivor and steer them into a Spitter's acid patch.
As the Jockey, ride the Survivors twice in a single life.
As the Jockey, ride a Survivor for more than 12 seconds.
As the Spitter, hit every Survivor with a single acid patch.
Kill 10 swampy Mudmen while they are in the water.
Kill 15 Infected with a single grenade launcher blast.
Ignite 50 Common Infected with incendiary ammo.
Survive the Parish campaign.
Deploy an ammo upgrade and have your team use it.
Kill 100 Common Infected with the chainsaw.
Decapitate 200 Infected with a melee weapon.
Kill a Jockey within 2 seconds of it jumping on a Survivor.
Use every melee weapon to kill Common Infected.
Survive the Hard Rain campaign.
Kill one of each Uncommon Infected.
Survive the Swamp Fever campaign.
Finish a campaign using only melee weapons.
Survive the Dark Carnival campaign.
Use a bile bomb on a Tank.
Spread cheer by helping a free holiday player survive a campaign.
Survive the Dead Center campaign.
Plays games with free weekend players and helps them survive a campaign.
Kill a Spitter before she is able to spit.
Play 5 full games of Scavenge on The Port.
As the Charger, grab a Survivor and crash them through 8 chairs at the wedding.
Play 6 Mutations.
Using the M60, kill 25 infected without letting go of the trigger.
Kill a Tank only with damage from the original Survivors.
Open 5 foot lockers.
Collect 10 items dropped by a Fallen Survivor.
Play the new Midnight Riders song on a jukebox.
Survive The Passing Campaign.
Knock off the heads of 18 infected with the golf club.
Have all 3 generators running at once in "The Sacrifice" finale.
As a Special Infected, incap someone who is trying to sacrifice themselves.
Kill a Special Infected with an exploding barrel.
Complete "The Sacrifice".
Have Bill sacrifice himself for the team.
Survive the Cold Stream campaign on any difficulty.
Play a Versus game on Dead Air from start to finish.
Collect three gifts dropped by Special Infected in Versus Mode.
Kill 53,599 infected. You made sure the dead won't rise anymore!
Earn a silver medal on every official survival map.
Earn a gold medal on every official survival map.
Earn a bronze medal on every official survival map
Destroy 20 gascans as the Spitter.
Kill 20 Jockeys with the shovel or pitchfork.
Kill a Witch using only a sharp melee weapon, without anyone getting incapacitated or killed.
Instantly kill a Survivor as the Charger.
As the Hunter, land a 25 damage pounce.
As the Spitter, spit on a Survivor who is pinned by a Hunter.
As the Spitter, spit on a Survivor who is pinned by a Charger.
As the Boomer, vomit on a Survivor without having direct line of sight with them.
Survive for 10 minutes on any official map in Versus Survival.
Escape Liberty Mall's Atrium before the first Tank appears
Rescue three Survivors from a single rescue closet.
Revive an incapacitated teammate while a Tank is nearby.
Destroy a Tank's rock in mid-air.
Kill a pouncing Hunter with a shotgun.
Kill the Witch bride with a single shotgun blast on expert difficulty.
Survive The Last Stand campaign on Expert Realism.
Discover the hidden room in the Last Stand campaign
Find the golden crowbars hidden in the Left 4 Dead 1 survival maps.
Complete The Last Stand campaign in 13 minutes or less, without any Survivors dying.
Survive The Last Stand campaign on any difficulty.
On the concert finale, survive until the helicopter arrives without leaving the stage
With a sharp melee weapon, cut a Smoker's tongue before he ensnares you.
Survive for 30 minutes on any official survival map.
Earn a gold medal on any official survival map.
Earn a silver medal on any official survival map.
Earn a bronze medal on any official Survival map.
If you are reading this achievement, Gabe Newell has successfully launched Gnome Chompski into space.