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