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