Left 4 Sonic

Survive the No Hope campaign.

Survive the Dead Toll campaign.

Survive the Death Air campaign.

Survive the Blood Sky campaign.

Survive the Crash Course campaign

Complete "The Sacrifice"

Kill a Smoker who has grabbed you with his tongue.

Have Classic Sonic sacrifice himself for the team.

Earn a Bronze medal in Survival mode on any official level.

Light a Witch with a Molotov.

You or another Survivor take no damage after being vomited on by a Boomer.

Revive 50 incapacitated Survivors.

Kill 53,595 Infected.

Kill a Special Infected with an exploding barrel.

Rescue a Survivor from a Smoker's tongue before they take damage.

Make 100 headshot kills.

Kill a Tank without it dealing any damage to a Survivor

Kill 10 Smokers as they are pulling helpless Survivors.

Rescue a Survivor trapped in a closet.

Shove a Hunter off of a pinned and helpless Survivor.

Light a Tank on fire with a Molotov

Stun a Tank with an explosion in the Crash Course campaign.

Save another Survivor from a Special Infected while on the ground.

Win a Versus campaign of Crash Course.

Headshot a Hunter while he's leaping.

Shove a Boomer and then kill him without him splashing on anyone.

Leave a safe room to save an incapacitated teammate and bring them back safely.

Give pain pills to 10 Survivors.

Heal 25 Survivors with a first aid kit.

Kill a Witch with a single headshot.

Pounce two different Survivors in one life as a Hunter.

Pounce a Survivor for 25 points of damage in the Crash Course campaign.

Constrict two Survivors in one life as a Smoker.

Dole out 5000 total Survivor damage as a Special Infected.

Cover four Survivors with Boomer bile at once.

As an Infected, incapacitate a Survivor who has entered and left a safe room.

As a Tank, hit 20 Survivors with a car in the Crash Course campaign.

Finish a campaign without ever using a first aid kit on yourself.

Play an entire campaign with no Survivors taking friendly fire damage.

Blow up 20 Infected in a single explosion.

Have all three generators running at once in The Sacrifice finale.

Protect any Survivor from an attacking Infected 50 times.

Set 101 Infected on fire.

Kill a Witch without any Survivor taking damage from her.

Beat a campaign with all 4 Survivors.

Restart the generator within 30 seconds of it shutting off in the Crash Course campaign.

Heal a fellow Survivor when your own health is below 10.

Kill 5,359 Infected in the Crash Course campaign.

No Survivors take damage after contacting the rescue vehicle.

Kill 1000 Infected with a mounted machine gun.

Survive a campaign without being incapacitated.

Survive an entire campaign using only pistols.

Drag a Survivor 100 feet with your tongue as a Smoker.

Smoker pull a bile-covered Survivor until you hold him during Crash Course.

Your team wipes all Survivors after the rescue vehicle has opened in Crash Course.

Complete one round of Survival on The Last Stand.

Earn at least a Bronze medal on every official Survival level.

Earn at least a Silver medal on every official Survival level.

Earn a Silver medal in Survival mode on any official level.

Earn a Gold medal in Survival mode on any official level.

Your team incapacitates three Survivors within five seconds in the Crash Course campaign.

As a Special Infected, incap someone who is trying to sacrifice themselves.

Incapacitate or kill all four Survivors in one life as a Tank.

Survive all campaigns on Expert.

Survive any campaign on Expert.

Finish a campaign without being healed by a first aid kit.

Survive a campaign with no Survivors taking damage from Special Infected.

Earn a Gold medal on every official Survival level.