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.
Collect 100 gas cans in Scavenge.
Collect 15 gas cans in a single Scavenge round.
Revive 10 incapacitated Survivors while under the speed-boosting effects of adrenaline.
Form a team and beat an enemy team in 4v4 Versus or Scavenge.
In a Survival round, get a medal only using melee weapons.
Survive a campaign on Expert skill with Realism mode enabled.
As the Charger, grab a Survivor and smash them into the ground for a solid 15 seconds.
Make a Survivor drop a gas can during overtime.
As the Charger, grab a Survivor and carry them over 80 feet.
As the Jockey, ride a Survivor and steer them into a Spitter's acid patch.
In a Versus round, leave the saferoom to defibrillate a dead teammate.
As the Charger, bowl through the entire enemy team in a single charge.
Plays games with free weekend players and helps them survive a campaign.
Honk the noses of 10 Clowns.
Using a Molotov, burn a Clown leading at least 10 Common Infected.
Kill a Charger with a melee weapon while they are charging.
Kill a Spitter before she is able to spit.
Finish a campaign using only melee weapons.
Kill one of each Uncommon Infected.
Kill a Jockey within 2 seconds of it jumping on a Survivor.
Decapitate 200 Infected with a melee weapon.
Survive all campaigns on Expert.
Kill 10 swampy Mudmen while they are in the water.
Collect 10 vials of Boomer vomit from infected CEDA agents you have killed.
Kill 15 Infected with a single grenade launcher blast.
Ignite 50 Common Infected with incendiary ammo.
Deploy an ammo upgrade and have your team use it.
Revive 10 dead Survivors with the defibrillator.
Kill 100 Common Infected with the chainsaw.
Use a bile bomb on a Tank.
Use every melee weapon to kill Common Infected.
Kill a Tank with melee weapons.
Cross the bridge finale in less than three minutes.
Survive the Dead Center campaign.
Survive the Dark Carnival campaign.
Survive the Swamp Fever campaign.
Survive the Hard Rain campaign.
Survive the Parish campaign.
Navigate the impound lot and reach the cemetery safe room without tripping any alarms.
Rescue Gnome Chompski from the Carnival.
Navigate the sugar mill and reach the safe room without killing any Witches.
Defend yourself at the crashed airliner without taking damage.
As the Jockey, ride a Survivor for more than 12 seconds.
As the Jockey, ride the Survivors twice in a single life.
As the Spitter, hit every Survivor with a single acid patch.
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.
Prove you are stronger than Moustachio.
Prove you are faster than Moustachio.
Spread cheer by helping a free holiday player survive a campaign.
As the Charger, grab a Survivor and crash them through 8 chairs at the wedding.
Play 5 full games of Scavenge on The Port.
Survive The Passing Campaign.
Using the M60, kill 25 infected without letting go of the trigger.
Collect 10 items dropped by a Fallen Survivor.
Play 6 Mutations.
Knock off the heads of 18 infected with the golf club.
Play the new Midnight Riders song on a jukebox.
Kill a Tank only with damage from the original Survivors.
Open 5 foot lockers.
Have all 3 generators running at once in "The Sacrifice" finale.
As a Special Infected, incap someone who is trying to sacrifice themselves.
Complete "The Sacrifice".
Have Bill sacrifice himself for the team.
Kill a Special Infected with an exploding barrel.
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
Survive for 10 minutes on any official map in Versus Survival.
As the Hunter, land a 25 damage pounce.
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.
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.
Find the golden crowbars hidden in the Left 4 Dead 1 survival maps.
Survive The Last Stand campaign on Expert Realism.
Complete The Last Stand campaign in 13 minutes or less, without any Survivors dying.
Discover the hidden room in the Last Stand campaign
Kill 20 Jockeys with the shovel or pitchfork.
Survive The Last Stand campaign on any difficulty.
Kill a Witch using only a sharp melee weapon, without anyone getting incapacitated or killed.
Rescue three Survivors from a single rescue closet.
On the concert finale, survive until the helicopter arrives without leaving the stage
Kill the Witch bride with a single shotgun blast on expert difficulty.
Escape Liberty Mall's Atrium before the first Tank appears
Survive for 30 minutes on any official survival map.
Earn a gold medal on any official survival map.
With a sharp melee weapon, cut a Smoker's tongue before he ensnares you.
Kill a pouncing Hunter with a shotgun.
Destroy a Tank's rock in mid-air.
Revive an incapacitated teammate while a Tank is nearby.
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.