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 incapacitated Survivors while under the speed-boosting effects of adrenaline.
In a Versus round, leave the saferoom to defibrillate a dead teammate.
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.
Cause 25 gas can drops as a Special Infected.
Collect 100 gas cans in Scavenge.
Revive 10 dead Survivors with the defibrillator.
Survive a campaign on Expert skill with Realism mode enabled.
Plays games with free weekend players and helps them survive a campaign.
Make a Survivor drop a gas can during overtime.
Form a team and beat an enemy team in 4v4 Versus or Scavenge.
As the Charger, bowl through the entire enemy team in a single charge.
Survive all campaigns on Expert.
Spread cheer by helping a free holiday player survive a campaign.
As the Spitter, hit every Survivor with a single acid patch.
Stop the enemy team from collecting any gas cans during a Scavenge round.
Kill a Charger with a melee weapon while they are charging.
Use a bile bomb on a Tank.
As the Spitter, spit on a Survivor being choked by a Smoker.
Using a Molotov, burn a Clown leading at least 10 Common Infected.
Kill 15 Infected with a single grenade launcher blast.
Kill a Tank with melee weapons.
As the Charger, grab a Survivor and carry them over 80 feet.
Cross the bridge finale in less than three minutes.
Collect 10 vials of Boomer vomit from infected CEDA agents you have killed.
As the Charger, grab a Survivor and smash them into the ground for a solid 15 seconds.
As the Jockey, ride a Survivor for more than 12 seconds.
Collect 15 gas cans in a single Scavenge round.
Kill 10 swampy Mudmen while they are in the water.
Defend yourself at the crashed airliner without taking damage.
Navigate the sugar mill and reach the safe room without killing any Witches.
Prove you are faster than Moustachio.
Navigate the impound lot and reach the cemetery safe room without tripping any alarms.
Win a game of Scavenge.
In a Survival round, get a medal only using melee weapons.
Ignite 50 Common Infected with incendiary ammo.
Prove you are stronger than Moustachio.
Survive the Dark Carnival campaign.
Rescue Gnome Chompski from the Carnival.
Honk the noses of 10 Clowns.
Survive the Parish campaign.
Use every melee weapon to kill Common Infected.
Finish a campaign using only melee weapons.
Survive the Swamp Fever campaign.
Kill one of each Uncommon Infected.
Deploy an ammo upgrade and have your team use it.
Survive the Dead Center campaign.
Kill 100 Common Infected with the chainsaw.
Kill a Spitter before she is able to spit.
Decapitate 200 Infected with a melee weapon.
Survive the Hard Rain campaign.
Kill a Jockey within 2 seconds of it jumping on a Survivor.
As the Charger, grab a Survivor and crash them through 8 chairs at the wedding.
Play 5 full games of Scavenge on The Port.
Play the new Midnight Riders song on a jukebox.
Play 6 Mutations.
Kill a Tank only with damage from the original Survivors.
Open 5 foot lockers.
Knock off the heads of 18 infected with the golf club.
Collect 10 items dropped by a Fallen Survivor.
Using the M60, kill 25 infected without letting go of the trigger.
Survive The Passing Campaign.
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.
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 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
Instantly kill a Survivor as the Charger.
Complete The Last Stand campaign in 13 minutes or less, without any Survivors dying.
Escape Liberty Mall's Atrium before the first Tank appears
Survive The Last Stand campaign on Expert Realism.
Survive The Last Stand campaign on any difficulty.
Find the golden crowbars hidden in the Left 4 Dead 1 survival maps.
Kill 20 Jockeys with the shovel or pitchfork.
As the Spitter, spit on a Survivor who is pinned by a Charger.
Kill the Witch bride with a single shotgun blast on expert difficulty.
Survive for 10 minutes on any official map in Versus Survival.
As the Boomer, vomit on a Survivor without having direct line of sight with them.
Destroy 20 gascans as the Spitter.
With a sharp melee weapon, cut a Smoker's tongue before he ensnares you.
Destroy a Tank's rock in mid-air.
On the concert finale, survive until the helicopter arrives without leaving the stage
Kill a pouncing Hunter with a shotgun.
Survive for 30 minutes on any official survival map.
As the Hunter, land a 25 damage pounce.
Kill a Witch using only a sharp melee weapon, without anyone getting incapacitated or killed.
Revive an incapacitated teammate while a Tank is nearby.
Earn a bronze medal on any official Survival map.
Earn a gold medal on any official survival map.
Earn a silver medal on any official survival map.
Rescue three Survivors from a single rescue closet.
As the Spitter, spit on a Survivor who is pinned by a Hunter.
Discover the hidden room in the Last Stand campaign
If you are reading this achievement, Gabe Newell has successfully launched Gnome Chompski into space.