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