The list of Xbox 360 Achievements for Left 4 Dead 2 appear to have just "confirmed" the game's two, still-to-be-officially-announced final campaigns and revealed new items, new infected and... clown nose honking?!
The 50 new Achievements, newly listed at Xbox 360 Achievements, don't really venture into spoiler territory—there are no plot points revealed here—but we'll touch on the unrevealed stuff after this, just to appease the sensitive types.
The list of Achievements looks to verify the leaked campaign posters for "Dead Center" and "Hard Rain," possibly ordering them in sequence as the first and second-to-last campaigns in Left 4 Dead 2.
Also apparently confirmed is the Boomer Bile Bomb, a grenade weapon that looks to be gathered from slain infected CEDA agents. Our best guess is that the Bile Bomb works in the Survivors' favor, sending a horde of zombies after the target in a fashion similar to the Antlion pheromone weapon seen in Half-Life 2.
The Achievements also make mention of a defibrillator twice, which looks to revive dead Survivors.
Of course, the Achievements also reveal that Valve hasn't lost its touch for puns. Read through the full list for plenty of laffs.
PRICE CHOPPER - 20
Survive the Dead Center campaign.MIDNIGHT RIDER - 20
Survive the Dark Carnival campaign.RAGIN' CAJUN - 20
Survive the Swamp Fever campaign.WEATHERMAN - 20
Survive the Hard Rain campaign.BRIDGE BURNER - 20
Survive the Parish campaign.STILL SOMETHING TO PROVE - 35
Survive all campaigns on Expert.THE REAL DEAL - 35
Survive a campaign on Expert skill with Realism mode enabled.CONFEDERACY OF CRUNCHES - 30
Finish a campaign using only melee weapons.HEAD HONCHO - 15
Decapitate 200 Infected with a melee weapon.CLUB DEAD - 15
Use every melee weapon to kill Common Infected.CHAIN OF COMMAND - 15
Kill 100 Common Infected with the chainsaw.TANK BURGER - 30
Kill a Tank with melee weapons.SHOCK JOCK - 30
Revive 10 dead Survivors with the defibrillator.THE QUICK AND THE DEAD - 30
Revive 10 incapacitated Survivors while under the speed-boosting effects of adrenaline.ARMORY OF ONE - 15
Deploy an ammo upgrade and have your team use it.BURNING SENSATION - 15
Ignite 50 Common Infected with incendiary ammo.DISMEMBERMENT PLAN - 20
Kill 15 Infected with a single grenade launcher blast.SEPTIC TANK - 15
Use a bile bomb on a Tank.CRASS MENAGERIE - 30
Kill one of each Uncommon Infected.DEAD IN THE WATER - 20
Kill 10 swampy Mudmen while they are in the water.ROBBED ZOMBIE - 15
Collect 10 vials of Boomer vomit from infected CEDA agents you have killed.CL0WND - 15
Honk the noses of 10 Clowns.FRIED PIPER - 15
Using a Molotov, burn a Clown leading at least 10 Common Infected.LEVEL A CHARGE - 15
Kill a Charger with a melee weapon while they are charging.ACID REFLEX - 15
Kill a Spitter before she is able to spit.A RIDE DENIED - 15
Kill a Jockey within 2 seconds of it jumping on a Survivor.STACHE WHACKER - 15
Prove you are faster than Moustachio.GONG SHOW - 15
Prove you are stronger than Moustachio.GUARDIN' GNOME - 30
Rescue Gnome Chompski from the Carnival.WING AND A PRAYER - 30
Defend yourself at the crashed airliner without taking damage.SOB STORY - 30
Navigate the sugar mill and reach the safe room without killing any Witches.VIOLENCE IN SILENCE - 30
Navigate the impound lot and reach the cemetery safe room without tripping any
alarms.BRIDGE OVER TREBLED SLAUGHTER - 30
Cross the bridge finale in less than three minutes.HEARTWARMER - 20
In a Versus round, leave the saferoom to defibrillate a dead teammate.STRENGTH IN NUMBERS - 15
Form a team and beat an enemy team in 4v4 Versus or Scavenge.QUALIFIED RIDE - 15
As the Jockey, ride a Survivor for more than 12 seconds.BACK IN THE SADDLE - 15
As the Jockey, ride the Survivors twice in a single life.RODE HARD, PUT AWAY WET - 20
As the Jockey, ride a Survivor and steer them into a Spitter's acid patch.GREAT EXPECTORATIONS - 15
As the Spitter, hit every Survivor with a single acid patch.A SPITTLE HELP FROM MY FRIENDS - 15
As the Spitter, spit on a Survivor being choked by a Smoker.SCATTERING RAM - 20
As the Charger, bowl through the entire enemy team in a single charge.MEAT TENDERIZER - 20
As the Charger, grab a Survivor and smash them into the ground for a solid 15 seconds.LONG DISTANCE CARRIER - 15
As the Charger, grab a Survivor and carry them over 80 feet.BEAT THE RUSH - 15
In a Survival round, get a medal only using melee weapons.HUNTING PARTY - 15
Win a game of Scavenge.GAS GUZZLER - 20
Collect 100 gas cans in Scavenge.CACHE AND CARRY - 20
Collect - 15 gas cans in a single Scavenge round.SCAVENGE HUNT - 15
Stop the enemy team from collecting any gas cans during a Scavenge round.FUEL CRISIS - 15
Make a Survivor drop a gas can during overtime.
GAS SHORTAGE - 30
Cause 25 gas can drops as a Special Infected.
Left 4 Dead 2 Achievement List [Xbox360Achievements.org - thanks, Chris!]