Full list of all 93 Back 4 Blood achievements. It takes around 120-150 hours to unlock all of the achievements in the base game on Windows.
The base game contains 55 achievements, and there are 3 DLC packs containing 38 achievements.
Complete The Armory.
Complete Blue Dog Hollow.
Complete all Act 1 maps on Recruit difficulty or higher.
Complete The Dark Before The Dawn.
Complete Search & Rescue.
Kill at least one of each non-boss Mutation.
Heal a teammate.
Kill 15 enemies while downed.
Complete The Devil's Return.
Complete a map without ever triggering a horde from Reekers, Birds, Snitches, or alarms.
Drop some ammo for a teammate.
Play 25 cards in a single match.
Revive a fallen teammate.
Form a party in Fort Hope.
Complete a level while getting at least 50 kills with melee weapons.
Kill a Monstrous Breaker after removing all of its armor.
Make a Breaker hurt itself.
Kill a Snitch without it alerting the horde.
Complete a mission without any players being incapacitated or killed.
Rescue a teammate from a cocoon.
Safely descend the ladder in the construction zone in Resurgence.
Good luck out there, you're gunna need it.
Complete all Act 1 maps on Veteran difficulty or higher.
Complete all Act 1 maps on Nightmare difficulty.
Complete Plan B.
Complete Job 10:22.
Complete all Act 2 maps on Recruit difficulty or higher.
Complete all Act 2 maps on Veteran difficulty or higher.
Complete all Act 2 maps on Nightmare difficulty.
Complete Dr. Rogers' Neighborhood.
Complete Remnants.
Complete all Act 3 maps on Recruit difficulty or higher.
Complete all Act 3 maps on Veteran difficulty or higher.
Complete all Act 3 maps on Nightmare difficulty.
Complete Act 4 on Recruit difficulty or higher.
Complete Act 4 on Veteran difficulty or higher.
Complete Act 4 on Nightmare difficulty.
Kill 53,600 Ridden over your career.
Kill an Ogre with the Howitzer.
Spend your first Supply Point.
Complete a mission with each of the original Cleaners.
Complete a map without any players on the team killing a single Ridden.
Defend the jukebox in Bar Room Blitz without it breaking.
Kill 10 Ridden with Bob's Arm.
Win a game in Swarm Mode.
Find the secret in The Devil's Return.
Find the secret in Search & Rescue.
Find the secret in The Dark Before the Dawn.
Find the secret in Blue Dog Hollow.
Find the secret in The Armory.
Find the secret in Plan B.
Find the secret in Job 10:22.
Find the secret in Dr. Rogers' Neighborhood.
Find the secret in Remnants.
Find the secret in The Abomination.
Get a kill with a Legendary Weapon.
Kill each of the Warped Ridden
Earn some Skull Totems.
Kill 10 Ridden with a Skull Totem.
Find the Secret in Blood Stream.
Complete All Ridden Hives.
Find the Secret in The Nursery.
Find the Secret in Sunken Passages.
Find the Secret in The Cut.
Find the Secret in Brood Lair.
Find the Secret in 300 Below.
Find the Secret in Caustic Cesspool.
Kill all variants of the Sentinel.
Complete all Act 6 maps on Recruit difficulty or higher.
Complete all Act 6 maps on Veteran difficulty or higher.
Complete all Act 6 maps on Nightmare difficulty or higher.
Complete all Act 6 maps on No Hope difficulty.
Find the Secret in Act 6.
Land a final blow on a Boss Mutation with the LAW.
Set an enemy on fire with the Flamethrower, while also being on fire.
Play Trial of the Worm for the first time.
Earn a score of at least 100,000 in Trial of the Worm.
Complete a map in Trial of the Worm with a total modifier of at least x20.
Defeat The Harbinger without using the LAW.
Blow up a Food Item with the LAW.