Left 4 Dead
2,774
(1,500)

Left 4 Dead

4.2 from 13367 votes
 

There are a maximum of 65 Left 4 Dead achievements (50 without DLC) worth 2,774 (1,500)

142,692 tracked gamers have this game, 7,145 have completed it (5.01%) | 622 want to boost

AvatarSeipher
78%

AvatarSeipher1,335 (900)

First played on 02 Dec 08

47 achievements out of 60 won (inc 1 of 10 DLC achievements)

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Left 4 Dead Achievements

Unbreakable
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement. Finish a campaign without ever being healed.
Big Drag
There is a guide to this achievementBig Drag32 (20)
1 gamer needs helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Drag a Survivor 100 feet with your tongue.
Barf Bagged
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Cover four Survivors with Boomer bile at once.
Double Jump
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Pounce two different Survivors in one life as a Hunter.
All 4 Dead
There is a guide to this achievementAll 4 Dead61 (30)
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Kill all four Survivors in one life while playing as a Tank.
Lamb 2 Slaughter
1 gamer needs helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. As an Infected, incap a Survivor who has entered and left a safe room.
Back 2 Help
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Leave a safe room to save an incapped teammate and bring them back safely.
Stomach Upset
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement. All Survivors complete a campaign without being vomited on.
Dead Wreckening
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Dole out 5000 total Survivor damage as a Special Infected.
Red Mist
There is a guide to this achievementRed Mist45 (20)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Kill 1000 Infected with a mounted machine gun.
Do Not Disturb
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Sneak past all Witches in a campaign without disturbing one.
Safety First
1 gamer needs helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Play an entire campaign with no Survivors taking friendly fire damage.
Stand Tall
There is a guide to this achievementStand Tall28 (20)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement. Survive a campaign without being incapacitated.
Man vs Tank
1 gamer needs helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Single-handedly kill a Tank.
Untouchables
1 gamer needs helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement. No Survivors take damage after contacting the rescue vehicle.
Helping Hand
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Revive 50 incapacitated Survivors.
Jump Shot
There is a guide to this achievementJump Shot28 (20)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement. Headshot a Hunter while he's leaping.
Akimbo Assassin
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Survive an entire campaign using only pistols.
Dead Stop
There is a guide to this achievementDead Stop12 (10)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Punch a Hunter as he is pouncing.
Field Medic
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Heal 25 Survivors with a first aid kit.
101 Cremations
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Set 101 Infected on fire.
Pharm-assist
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Give pain pills to 10 Survivors.
Burn the Witch
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Light a Witch with a Molotov.
Cr0wnd
There is a guide to this achievementCr0wnd47 (30)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Kill a Witch with a single headshot.
Witch Hunter
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Kill a Witch without any Survivor taking damage from her.
Toll Collector
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Main Storyline - These achievements are gained automatically by progressing through the main game mode. Survive the Death Toll campaign.
Spinal Tap
There is a guide to this achievementSpinal Tap12 (10)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Kill an Infected with a single blow from behind.
Clean Kill
There is a guide to this achievementClean Kill13 (10)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Shove a Boomer and then kill him without him splashing on anyone.
Pyrotechnician
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Blow up 20 Infected in a single explosion.
Grim Reaper
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Main Storyline - These achievements are gained automatically by progressing through the main game mode. Survive the Blood Harvest campaign.
Tankbusters
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Kill a Tank without it dealing any damage to a Survivor.
Dead Giveaway
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Heal a fellow Survivor when your own health is below 10.
Tongue Twister
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Free yourself from a Smoker who has grabbed you with his tongue.
Brain Salad
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Make 100 headshot kills.
Mercy Killer
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Main Storyline - These achievements are gained automatically by progressing through the main game mode. Survive the No Mercy campaign.
No Smoking Section
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Kill 10 Smokers as they are pulling helpless Survivors.
Blind Luck
There is a guide to this achievementBlind Luck21 (20)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. You or another Survivor take no damage after being vomited on by a Boomer.
Chain Smoker
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Constrict two Survivors in one life as a Smoker.
My Bodyguard
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Protect any Survivor from an attacking Infected 50 times.
Ground Cover
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Save another Survivor from a Special Infected while on the ground.
Dead Baron
There is a guide to this achievementDead Baron18 (15)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Main Storyline - These achievements are gained automatically by progressing through the main game mode. Survive the Dead Air campaign.
No-one Left Behind
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Beat a campaign with all 4 Survivors.
Hero Closet
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Rescue a Survivor trapped in a closet.
Hunter Punter
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Shove a Hunter off of a pinned and helpless Survivor.
Towering Inferno
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Light a Tank with a Molotov.
Drag and Drop
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Rescue a Survivor from a Smoker's tongue before he takes damage.
Zombie Genocidest
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time.Time Consuming - These achievements require at least 20 hours of play time to obtain. Kill 53,595 Infected.
Zombicidal Maniac
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Difficulty Specific - These achievements require that the game be played on a certain difficulty level. Survive any campaign on Expert.
What Are You Trying to Prove?
4 gamers need helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Difficulty Specific - These achievements require that the game be played on a certain difficulty level. Survive all campaigns on Expert.
Nothing Special
2 gamers need helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Survive a campaign with no Survivors taking damage from Special Infected.

Add-on: Crash Course

Crash Course
559
(250)

Crash Course

Xbox LIVE Store

40,933 tracked gamers have this dlc pack

There are a maximum of 10 achievements worth 559 (250)

There is 1 review

Crash-proof
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Main Storyline - These achievements are gained automatically by progressing through the main game mode. Survive the Crash Course Campaign.
Quick Power
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Time Sensitive - These achievements can be obtained by playing the game or performing actions at certain times or within a time limit. Restart the generator within 30 seconds of it shutting off in the Crash Course campaign.
The Littlest Genocide
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time. Kill 5,359 Infected in the Crash Course campaign.
Smash Hit
There is a guide to this achievementSmash Hit58 (25)
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Win a Versus campaign of Crash Course.
Truck Stop
There is a guide to this achievementTruck Stop86 (35)
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Your team wipes all Survivors after the escape vehicle has opened in Crash Course.
20 Car Pile-up
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Cumulative - These achievements are obtained by repeatedly performing the same action or set of actions over time.Buggy - - These achievements may unlock after the requirements have been met or not at all. As a Tank hit 20 Survivors with a car in the Crash Course campaign.
Jumpin' Jack Smash
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Pounce a Survivor for 25 points of damage in the Crash Course campaign.
Slippery Pull
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Smoker pull a bile-covered Survivor until you hold him during Crash Course.
Tank Stumble
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Stun a Tank with an explosion in the Crash Course campaign.
Wipefest
There is a guide to this achievementWipefest78 (35)
Online/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Time Sensitive - These achievements can be obtained by playing the game or performing actions at certain times or within a time limit. Your team incapacitates three Survivors within five seconds in the Crash Course campaign.

Add-on: The Sacrifice

The Sacrifice
568
(250)

The Sacrifice

Xbox LIVE Store

11,800 tracked gamers have this dlc pack

There are a maximum of 5 achievements worth 568 (250)

There are 2 reviews

Supreme Sacrifice
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.Main Storyline - These achievements are gained automatically by progressing through the main game mode. Complete "The Sacrifice".
Kill Bill
There is a guide to this achievementKill Bill99 (50)
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Have Bill sacrifice himself for the team.
Barrel Rolled
Online/Offline - These achievements can be obtained in either an online or offline mode.Single Player - These achievements can be obtained by a single player.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. Kill a Special Infected with an exploding barrel.
Chaos Generator
Online/Offline - These achievements can be obtained in either an online or offline mode.Cooperative + - These achievements can be obtained by two or more players and everyone who has met the requirements will earn the achievement.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement.3+ Players Required - These achievements require between three to five participating players in order for anyone to obtain it. Have all 3 generators running at once in "The Sacrifice" finale.
Sacrifizzle
There is a guide to this achievementSacrifizzle131 (50)
1 gamer needs helpOnline/Offline - These achievements can be obtained in either an online or offline mode.Versus + - These achievements can be obtained in a face off game mode by two or more players and everyone who has met the requirements will earn the achievement. As a Special Infected, incap someone who is trying to sacrifice themselves.