Full list of all 120 Darkest Dungeon achievements. It takes around 200 hours to unlock all of the achievements in the base game on Windows.
The base game contains 69 achievements, and there are 3 DLC packs containing 51 achievements.
Defeat the brigand Vvulf
Lose a Legendary (Level 6) hero
Have a character survive 5 attacks at Death's Door in a single combat
Fully upgrade a hero's weapons and armor
Fully upgrade the Blacksmith
Kill the Shrieker
Fully upgrade at least four of a hero's skills
Complete a long quest
Fully upgrade the Guild
Start a quest with all four heroes of Resolve Level 6
Reach week 52
Raise 4 heroes to Resolve Level 6
Learn a new Camping skill
Raise a hero to Resolve Level 6
Slay 1000 enemies
Complete 25 quests
Walk 500 steps with one hero
Defeat 100 Unholy enemies
Slay a Shambler
Defeat 100 Beast enemies
Defeat 100 Eldritch enemies
Kill 50 enemies with one hero
Dismiss your first hero
Collect at least 30 heirlooms from a single quest
Collect at least 20,000 gold from a single quest
Defeat 100 Human enemies
Complete 10 quests
Complete a quest in all four regions
Upgrade a Combat skill
Slay your first boss
Complete a medium quest
Remove a Quirk in the Sanitarium
Treat a hero in the Abbey
Abandon a quest
Treat a hero in the Tavern
Lose your first hero
Lose your first hero to heart attack
Complete a quest
Visit the Graveyard
Reach the Estate
Start a Darkest Dungeon quest with four heroes of resolve level 0
Complete a dungeon with all 4 heroes afflicted
Have one of each class on your roster
Lock a positive Quirk in the Sanitarium
Fully upgrade the Tavern
Fully upgrade the Abbey
Fully upgrade the Town
Reach week 104
Lose a hero to hunger
Lose a hero to Wilbur
Lose a hero to a Maggot
Lose a hero to a trap
Lose a hero to an obstacle
Lose all four heroes on a Darkest Dungeon quest
First party wipe
Party wipe on a boss
Acquire all your Ancestor's Trinkets
Complete the game with default difficulty options
Kill all bosses
Complete all Caretaker Goals
Complete the game
Complete the game within 99 Weeks
Kill any boss with only one hero remaining
Kill any boss with a party of four afflicted heroes
Complete the game on Stygian
Dismas and Reynauld Made it to the final Darkest Dungeon Quest
Complete the game on Radiant
Kill Squiffy Ghast, Swine Skiver, Bone Bearer and Hateful Virago
Kill a Squiffy Ghast with a Jester
Defeat the Baron
Defeat the Viscount
Defeat the Countess
Get infected by the Crimson Curse
Collect your first Trinket Set
Build your first district building
Build The Red Hook
Recruit a flagellant
Collect The Invitation
Lose a hero to Wasting Away from the Curse
Kill an ally while under the Curse
Contract the Crimson Curse via contagion
Defeat the Fanatic
Rescue someone
Have your entire roster affected by the crimson curse
Reach Death's Door From Farmhand's Riposte
Acquire Mildred's Locket Trinket
Complete The First Farmstead Quest
Defeat the Miller
Defeat the Sleeper
Collect All of Color of Madness Trinkets
Build the Windmill
Get 100 Kills
Get 200 Kills
Get 300 Kills
Defeat the Sleeper With 2 Afflicted, 2 Virtuous Heroes
Gain the Refracted Affliction
Fight Every Wondering Boss in Endless
Defeat the Thing From The Stars
Kill the Sleeper's Herald With a Riposte
Use The Shard Dust Provision
All 4 Heroes Dodge the Miller's Reaping
Earn 200 Shards In One Endless Run
Lose a Hero Equipped with the Coat of Many Colors
Lose a Hero Equipped with the Miller's Pipe
Play your first match in the Butcher's Circus
Cause an enemy hero to have a heart attack
Kill each hero class in the Butcher's Circus
Win a match in the dueling grounds
Daze 10 enemies in the Butcher's Circus
Win a match using ONLY stress against your enemies
Have a hero survive 5 death's door checks in a single match
Have a single hero deal deathblows to 4 enemies in a single match
Kill an enemy hero in the first round of a match
Have a single hero survive 4 heart attacks in a single match
Win a match without using any trinkets
Win 100 matches in the Butcher's Circus
Cause 150 heart attacks in the Butcher's Circus
Kill 600 enemies in the Butcher's Circus
Reach the max Prestige level in the Butcher's Circus
Win any 10 matches without losing any heroes