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