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