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