The The Crimson Court Add-on for Darkest Dungeon has 15 achievements.
Defeat the Baron
Defeat the Fanatic
Build your first district building
Rescue someone
Collect The Invitation
Contract the Crimson Curse via contagion
Get infected by the Crimson Curse
Recruit a flagellant
Defeat the Viscount
Defeat the Countess
Collect your first Trinket Set
Build The Red Hook
Lose a hero to Wasting Away from the Curse
Kill an ally while under the Curse
Have your entire roster affected by the crimson curse