- We Have Ourselves a Cowboy
Hold dual 9mm, dual hand cannons and Dual Revolvers
- Spec Ops
Kill 12 clots with one magazine without reloading (MK23)
- Attempting Re-entry
Beat Moonbase on Hard Difficulty
- Merry Friggin Christmas
[2010 Xmas] Kill the Christmas Patriarch.
- Nail'd!
Kill 4 Stalkers in a game with the Vlad9000 Nailgun
- Italian Meat Pasta
Kill 12 zeds with a full magazine from the Combat Shotgun
- Carving The Jack O' Lantern
Decapitate a burning Halloween specimen in Bedlam
- British Superiority
Kill a zed each with both the Bullpup and FN-Fal
- Combat Medic
Kill a zed that has injured a player (M7A3 rifle)
- Historical Remnants
Kill 6 Zeds with one magazine on an MKb42, without reloading
- I love ze Healing not ze Hurting
Heal others for 3000 points of health with the MP5 SMG
- Slight Drip
Win a Long Game on Waterworks on Normal Difficulty.
- Killer Junior
Kill 20 crawlers in mid-air with the M79.
- Thin-Ice Pirouette
Complete 10 Waves when the Rest of your Team has Died.
- Master Surgeon
As a Medic, Kill 8 Specimens using a Knife in a Single Wave.
- Healing Touch
Heal 200 teammates with the MP7's medication dart.
- Waste Land
Win a Long Game on Biohazard on Hard Difficulty.
- Departure Gallery
Win a Long Game on Departed on Normal Difficulty.
- The Boss
Win a Long Game on Offices on Normal Difficulty.
- Warehouse Janitor
Win a Long Game on Crash on Normal Difficulty.
- Snow Cone
Beat Ice Cave on Normal Difficulty
- Back to Work
[2010 Xmas] Kill 20 Christmas Clots in one wave.
- Bloody Yanks
Kill 1 specimen ONLY while expending a full M4 Assault Rifle magazine
- Who Brings a Gun to a Snow Ball Fight?
[2010 Xmas] Kill a Christmas Husk with any Pistol.
- Eggnog Anyone?
[2010 Xmas] Get covered in Christmas Bloat Bile and live for 10 seconds on Hard, Suicidal, or Hell on Earth.
- Feeling Lucky?
Kill a specimen with every shot from your Revolver for one magazine
- A Bloody Christmas Carol
Kill 15 XMas Clots, 5 xmas Stalkers, 5 XMas Crawlers, 1 XMas Siren and 1 XMas Bloat.
- Windjammer Enthusiast
Survive 10 seconds after being screamed at by a Circus Siren on Hard or above.
- Lifting a Dumbell
Kill a Circus Husk with a LAW.
- Punk'd
Unlock 10 of the 13 Circus Achievements along with any Abusement Park achievement.
- Flea Circus
Win a Long Game on Abusement Park on Normal Difficulty.
- Getting Chunky
Obliterate 10 Zeds at once with the Pipe Bomb.
- Ringmaster
Kill the "Ring Leader" (Circus Patriarch)
- Quarter Pounder With Ease
Turn 5 Fleshpounds into Giblets.
- The Big Hunt
Kill a Circus Scrake with a Crossbow.
- Elephant Gun
Land the killing blow on a Circus Fleshpound with a Pistol.
- Small Hands
Kill 3 Circus Clots in a wave with the Lever Action Rifle.
- Burning up the Midway
Kill 10 Circus Clots with a Fire-based weapon.
- Clearing Clown Alley
Kill 5 Circus Bloats in one game.
- Taking Down the Big Top
Kill 4 Circus Zeds in 1 ZED time chain with a Melee weapon.
- Seeing Double
Kill 5 Circus Crawlers with a Bullpup in one wave.
- Sparring with a Master
Kill a Circus Gorefast with a Melee weapon.
- Pub Crawl
Win a Long Game on West London on Normal Difficulty.
- Golden Potato
Get into GLaDOS' core on Aperture.
- Science Got Done
Win a Long Game on Aperture on Normal Difficulty.
- Too Close For Comfort
Finish off a Fleshpound using a Melee Attack.
- Lab Cleaner
Win a Long Game on Biotics Lab on Normal Difficulty.
- Random Axe of Kindness
Kill 15 Specimens with a Fire Axe in a Single Wave.
- Keep Those Sneakers Off the Floor!
Kill 20 Stalkers with Explosives.
- It's What's Inside That Counts
Turn 500 Specimens into Giblets.
- Experimentilottacide
Kill 10,000 Specimens.
- Careful Spender
Kill 4 Specimens with a Single Shot from a Hunting Shotgun.
- Fascist Dietitian
Kill 200 Bloats.
- Homer's Heroes
Kill 100 Sirens.
- Flaming Hell, That was Close
As Firebug, kill the Husk with the Flamethrower before he hurts anyone.
- The L.A.W. That Broke The Camel's Back
Deliver the Killing Blow to the Patriarch with a L.A.W. Rocket.
- Self Medicator
In Co-op Mode, Use Syringe on Yourself 100 Times.
- Philanthropist
Give 1,000 Pounds to Teammates who have 50% of Your Cash or Less.
- I Like To Watch
Aquire 5 Minutes of "Zed-Time".
- Experimentimillicide
Kill 1,000 Specimens.
- Let Them Burn
Get 1000 points of burn damage with the MAC-10.
- Neighborhood Watch
Win a Long Game on Suburbia on Normal Difficulty.
- Chicken Farmer
Win a Long Game on Farm on Normal Difficulty.
- Straight Rush
Kill the Patriarch Before he has a Chance to Heal.
- It's Not Easy Being Greasy
Cause a Specimen to Die by Luring them into Bloat Acid.
- Experimenticenticide
Kill 100 Specimens.
- Social Outburst
Kill 8 Specimens with One Grenade.
- Dignity for the Dead
Kill 10 Specimens Feeding on Dead Teammates Corpses.
- Duke of the Manor
Win a Long Game on Manor on Hard Difficulty.
- Cattle Farmer
Win a Long Game on Farm on Hard Difficulty.
- The Hard War
Complete a Long Game on all 5 Core Maps on Hard Difficulty.
- Suicidal Pub Crawl
Win a Long Game on West London on Suicidal Difficulty.
- Emperor of the Manor
Win a Long Game on Manor on Suicidal Difficulty.
- Alligator Farmer
Win a Long Game on Farm on Suicidal Difficulty.
- Mad Boss
Win a Long Game on Offices on Suicidal Difficulty.
- Lab Professor
Win a Long Game on Biotics Lab on Suicidal Difficulty.
- The Completely Suicidal War
Complete a Long Game on all 5 Core Maps on Suicidal Difficulty.
- Steel Worker
Win a Long Game on Foundry, on Hard Difficulty.
- Man of Steel
Win a Long Game on Foundry, on Suicidal Difficulty.
- Gone Mental
Win a Long Game on Bedlam, on Hard Difficulty.
- Complete Barking
Win a Long Game on Bedlam, on Suicidal Difficulty.
- Raccoon King of the Dark Forest
Win a Long Game on Wyre, on Hard Difficulty.
- Bear King of the Dark Forest
Win a Long Game on Wyre, on Suicidal Difficulty.
- Summer of 2009
Complete a Long Game on all 3 Summer 2009 maps on Hard Difficulty.
- And Back to School
Complete a Long Game on all 3 Summer 2009 maps on Suicidal Difficulty.
- Explosive Personality
As Demolitions, kill 1000 Specimens with the Pipebomb.
- Hellish Pub Crawl
Win a Long Game on West London on Hell on Earth Difficulty.
- Demonic King of the Manor
Win a Long Game on Manor on Hell on Earth Difficulty.
- Demon Farmer
Win a Long Game on Farm on Hell on Earth Difficulty.
- Boss from Hell
Win a Long Game on Offices on Hell on Earth Difficulty.
- Scientist from Hell
Win a Long Game on Biotics Lab on Hell on Earth Difficulty.
- Diablo Steel Man
Win a Long Game on Foundry on Hell on Earth Difficulty.
- Commit-ed for life
Win a Long Game on Bedlam on Hell on Earth Difficulty.
- Wolf King of the Dark Forest
Win a Long Game on Wyre on Hell on Earth Difficulty.
- Waste of Space
Win a Long Game on Biohazard on Suicidal Difficulty.
- Wasted
Win a Long Game on Biohazard on Hell on Earth Difficulty.
- Warehouse Forklift Operator
Win a Long Game on Crash on Hard Difficulty.
- Warehouse Foreman
Win a Long Game on Crash on Suicidal Difficulty.
- Warehouse Manager
Win a Long Game on Crash on Hell on Earth Difficulty.
- Departure Lounge
Win a Long Game on Departed on Hard Difficulty.
- Departure Gate
Win a Long Game on Departed on Suicidal Difficulty.
- Dear Departed
Win a Long Game on Departed on Hell on Earth Difficulty.
- Missed Connection
Win a Long Game on Filth's Cross on Hard Difficulty.
- Train Wreck
Win a Long Game on Filth's Cross on Suicidal Difficulty.
- Pile Up
Win a Long Game on Filth's Cross on Hell on Earth Difficulty.
- Gimme a Plaster!
Win a Long Game on Hospital Horrors on Normal Difficulty.
- That Bloody Well Hurts!
Win a Long Game on Hospital Horrors on Hard Difficulty.
- I'm Dying Here!
Win a Long Game on Hospital Horrors on Suicidal Difficulty.
- Not Dead Yet!
Win a Long Game on Hospital Horrors on Hell on Earth Difficulty.
- Ice Cube
Win a Long Game on Icebreaker on Normal Difficulty.
- Crushed Ice
Win a Long Game on Icebreaker on Hard Difficulty.
- Iceberg
Win a Long Game on Icebreaker on Suicidal Difficulty.
- Comet
Win a Long Game on Icebreaker on Hell on Earth Difficulty.
- Gone Camping
Win a Long Game on Mountain Pass on Hard Difficulty.
- Mountaineer
Win a Long Game on Mountain Pass on Suicidal Difficulty.
- Park Ranger
Win a Long Game on Mountain Pass on Hell on Earth Difficulty.
- Private Security
Win a Long Game on Suburbia on Hard Difficulty.
- Vigilante
Win a Long Game on Suburbia on Suicidal Difficulty.
- SWAT
Win a Long Game on Suburbia on Hell on Earth Difficulty.
- Burst Pipe
Win a Long Game on Waterworks on Hard Difficulty.
- Pressure Failure
Win a Long Game on Waterworks on Suicidal Difficulty.
- Floodgate to Hell
Win a Long Game on Waterworks on Hell on Earth Difficulty.
- Piece of Cake
Complete all new map achievements on Normal Difficulty.
- Pound Cake
Complete all new map achievements on Hard Difficulty.
- Fruit Cake
Complete all new map achievements on Suicidal Difficulty.
- Devil Cake
Complete all new map achievements on Hell On Earth Difficulty.
- Walking in A Winter Horror Land
Win a Long Game on Santa's Evil Lair on Normal Difficulty.
- Silent Night, Evil Night
Win a Long Game on Santa's Evil Lair on Hard Difficulty.
- I'm Dreaming of a Red Christmas
Win a Long Game on Santa's Evil Lair on Suicidal Difficulty.
- Grandma got Eaten by a Reindeer
Win a Long Game on Santa's Evil Lair on Hell on Earth Difficulty.
- Tis Better to Give than to Receive
[2010 Xmas] Drop 3 Tier 3 weapons for others (with which they kill at least one Christmas Zed).
- Still Alive
Win a Long Game on Aperture on Hard Difficulty.
- This is a Triumph
Win a Long Game on Aperture on Suicidal Difficulty.
- I'm Making a Note Here, Huge Success
Win a Long Game on Aperture on Hell on Earth Difficulty.
- Dog and Pony Show
Win a Long Game on Abusement Park on Hard Difficulty.
- 3 Ring Circus
Win a Long Game on Abusement Park on Suicidal Difficulty.
- On Top of the Big Top
Win a Long Game on Abusement Park on Hell on Earth Difficulty.
- Zed October
Win a Long Bedlam Match During the Halloween Event on Hard
- This is No Ordinary Rabbit!
Kill 25 Halloween Scrakes in Bedlam
- Rule The Roost
Get all 6 achievements and unlock Commando Chicken
- Demonic Road
Beat Hellride on Suicidal Difficulty
- Devil's Co-pilot
Beat Hellride on Hell on Earth Difficulty
- Have my axe
Kill 30 Fleshpounds with the Dwarfs!? axe with back attacks
- Amusing Death
Beat Moonbase on Suicidal Difficulty
- One Giant Leap (Back) for Mankind
Beat Moonbase on Hell on Earth Difficulty
- Modified Psychoacceleration Achiever
Beat Steamland on Hard Difficulty
- Fractional Neutron Activator
Beat Steamland on Suicidal Difficulty
- Advanced Omega Wave Resonance Explorer
Beat Steamland on Hell on Earth Difficulty
- Oscillating Hydrogen Transition Achiever
Beat Steamland in Objective Mode on Hard Difficulty
- Alpha Wave Osteooxidation Activator
Beat Steamland in Objective Mode on Suicidal Difficulty
- Tachyon Cytoneutralization Explorer
Beat Steamland in Objective Mode on Hell on Earth Difficulty
- Hide and go Puke
[2013 Summer] Destroy all the Pukey the Clown dolls
- Guardian Assault Protector
Protect the ringmaster during the defense mission so that he does not get hit more than 15 times
- Golden 3 Crown Note
Get all 3 gold bars without the carriers taking damage while they have them
- Mrs. Punkd
Get 4 of 6 of the 2013 Summer Event in-game level Achievements, one Standard and one Objective Mode map completion Achievement, plus the Punk'd Achievement to unlock Steampunk Mrs. Foster
- Longshoreman
Beat Fright Yard on Normal Difficulty
- Gang Crew
Beat Fright Yard on Hard Difficulty
- Stevedore
Beat Fright Yard on Suicidal Difficulty
- Wharfinger
Beat Fright Yard on Hell on Earth Difficulty
- Fork Lift Operator
Beat Fright Yard in Objective Mode on Normal Difficulty
- Truck Driver
Beat Fright Yard in Objective Mode on Hard Difficulty
- Crane Operator
Beat Fright Yard in Objective Mode on Suicidal Difficulty
- Shipping Magnate
Beat Fright Yard in Objective Mode on Hell on Earth Difficulty
- Claw Machine Master
Attach the crane hook within 125 seconds
- 777
Win Fuel on the first try
- Blinding Big Brother
Destroy all 30 Cameras
- Fire and Forget
Kill a Halloween Fleshpound and Scrake in the same explosion with the Seal Squeal Harpoon Bomber or the LAW
- Under The Weather
Use Bile or the Flamethrower to kill one of each Halloween Zed
- Cerberus
Beat Hell on Suicidal Difficulty
- Lucifer
Beat Hell on Hell on Earth Difficulty
- Brain Fart
Beat Forgotten on Normal Difficulty
- Agnosia
Beat Forgotten on Hard Difficulty
- Amnesia
Beat Forgotten on Suicidal Difficulty
- Dementia
Beat Forgotten on Hell on Earth Difficulty
- No Time for Love, Dr. Jones
Win a short round on KF-Hell playing as or with Harchier Spebbington
- Home Brewer
Beat Siren's Belch on Normal Difficulty
- Micro Brewer
Beat Siren's Belch on Hard Difficulty
- Master Brewer
Beat Siren's Belch on Suicidal Difficulty
- Trappist Monk
Beat Siren's Belch on Hell on Earth Difficulty
- Oktoberfest Master
Collect all the Beer Steins
- Squire
Beat Stronghold on Hard Difficulty
- Prince
Beat Stronghold on Suicidal Difficulty
- King
Beat Stronghold on Hell on Earth Difficulty
- Economy Comfort
Beat Transit on Hard Difficulty
- Business Class
Beat Transit on Suicidal Difficulty
- First Class
Beat Transit on Hell on Earth Difficulty
- Day-trip
Beat Transit in Objective Mode on Normal Difficulty
- Long weekend
Beat Transit in Objective Mode on Hard Difficulty
- Serious vacation
Beat Transit in Objective Mode on Suicidal Difficulty
- Moved to Paris!
Beat Transit in Objective Mode on Hell on Earth Difficulty
- Nitro Boost!
Transit - Get the Nitro to the Objective in 135 seconds or less
- Totally Metal
Transit - Kill 250 Zeds before completing the welding objective
- Multi-pass
Transit - Pick up the door key
- Science Hater
Transit - Destroy all the DNA vials
- Doctor WHO??
Transit - Get all Objective achievements AND beat KFO Transit on Hard or above to unlock Dr Rachel Clamely.
- Rack 'em up
Beat Clandestine on Hard Difficulty
- Burned out
Beat Clandestine on Suicidal Difficulty
- Hangover from Hell
Beat Clandestine on Hell Difficulty
- Cave of Wonder
Beat ThrillsChills on Normal Difficulty
- Cavern of Pain
Beat ThrillsChills on Hard Difficulty
- Grotto of Terror
Beat ThrillsChills on Suicidal Difficulty
- Hollow of Horror
Beat ThrillsChills on Hell Difficulty
- All shook up
Destroy all (15) Snow Globes