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