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.
Revive 10 dead Survivors with the defibrillator.
Revive 10 incapacitated Survivors while under the speed-boosting effects of adrenaline.
Form a team and beat an enemy team in 4v4 Versus or Scavenge.
In a Versus round, leave the saferoom to defibrillate a dead teammate.
Survive all campaigns on Expert.
Survive a campaign on Expert skill with Realism mode enabled.
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.
Defend yourself at the crashed airliner without taking damage.
Navigate the sugar mill and reach the safe room without killing any Witches.
Kill a Charger with a melee weapon while they are charging.
Cross the bridge finale in less than three minutes.
Rescue Gnome Chompski from the Carnival.
Using a Molotov, burn a Clown leading at least 10 Common Infected.
In a Survival round, get a medal only using melee weapons.
Plays games with free weekend players and helps them survive a campaign.
Spread cheer by helping a free holiday player survive a campaign.
Finish a campaign using only melee weapons.
As the Spitter, spit on a Survivor being choked by a Smoker.
Kill a Tank with melee weapons.
Collect 100 gas cans in Scavenge.
Cause 25 gas can drops as a Special Infected.
As the Jockey, ride a Survivor and steer them into a Spitter's acid patch.
As the Spitter, hit every Survivor with a single acid patch.
As the Jockey, ride the Survivors twice in a single life.
As the Charger, grab a Survivor and smash them into the ground for a solid 15 seconds.
Survive the Dark Carnival campaign.
Collect 15 gas cans in a single Scavenge round.
As the Jockey, ride a Survivor for more than 12 seconds.
Collect 10 vials of Boomer vomit from infected CEDA agents you have killed.
Ignite 50 Common Infected with incendiary ammo.
Stop the enemy team from collecting any gas cans during a Scavenge round.
Make a Survivor drop a gas can during overtime.
Win a game of Scavenge.
Kill 15 Infected with a single grenade launcher blast.
Survive the Parish campaign.
Navigate the impound lot and reach the cemetery safe room without tripping any alarms.
Use every melee weapon to kill Common Infected.
Kill one of each Uncommon Infected.
Kill 10 swampy Mudmen while they are in the water.
Survive the Swamp Fever campaign.
Decapitate 200 Infected with a melee weapon.
Kill 100 Common Infected with the chainsaw.
Survive the Dead Center campaign.
Prove you are stronger than Moustachio.
Prove you are faster than Moustachio.
Honk the noses of 10 Clowns.
Survive the Hard Rain campaign.
Kill a Jockey within 2 seconds of it jumping on a Survivor.
Kill a Spitter before she is able to spit.
Deploy an ammo upgrade and have your team use it.
Use a bile bomb on a Tank.
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.
Survive The Passing Campaign.
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.
Kill a Tank only with damage from the original Survivors.
Open 5 foot lockers.
Play 6 Mutations.
Play 5 full games of Scavenge on The Port.
Have all 3 generators running at once in "The Sacrifice" finale.
As a Special Infected, incap someone who is trying to sacrifice themselves.
Complete "The Sacrifice".
Have Bill sacrifice himself for the team.
Kill a Special Infected with an exploding barrel.
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!
Survive for 10 minutes on any official map in Versus Survival.
Earn a gold medal on every official survival map.
Earn a silver medal on every official survival map.
Earn a bronze medal on every official survival map
Destroy 20 gascans as the Spitter.
Instantly kill a Survivor as the Charger.
As the Spitter, spit on a Survivor who is pinned by a Hunter.
With a sharp melee weapon, cut a Smoker's tongue before he ensnares you.
Kill a Witch using only a sharp melee weapon, without anyone getting incapacitated or killed.
Escape Liberty Mall's Atrium before the first Tank appears
Survive The Last Stand campaign on Expert Realism.
Kill a pouncing Hunter with a shotgun.
Kill 20 Jockeys with the shovel or pitchfork.
Kill the Witch bride with a single shotgun blast on expert difficulty.
As the Hunter, land a 25 damage pounce.
As the Spitter, spit on a Survivor who is pinned by a Charger.
Revive an incapacitated teammate while a Tank is nearby.
Destroy a Tank's rock in mid-air.
On the concert finale, survive until the helicopter arrives without leaving the stage
Rescue three Survivors from a single rescue closet.
Survive for 30 minutes on any official survival map.
As the Boomer, vomit on a Survivor without having direct line of sight with them.
Complete The Last Stand campaign in 13 minutes or less, without any Survivors dying.
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.
Discover the hidden room in the Last Stand campaign
Find the golden crowbars hidden in the Left 4 Dead 1 survival maps.
Survive The Last Stand campaign on any difficulty.
If you are reading this achievement, Gabe Newell has successfully launched Gnome Chompski into space.