Full list of all 48 Cult of the Lamb achievements. It takes around 15-20 hours to unlock all of the achievements in the base game on Windows.
The base game contains 37 achievements, and there are 2 DLC packs containing 11 achievements.
Sacrifice 10 Followers.
Unlock all tarot cards.
Unlock all fleeces.
Unlock all Follower Skins.
Beat Kallamar without taking damage.
Take confession.
Beat Shamura without taking damage.
Beat Heket without taking damage.
Beat Leshy without taking damage.
Have 666 gold coins.
Defeat the One Who Waits.
Defeat Kallamar.
Find all 5 locations.
Defeat all opponents in Knucklebones.
Unlock all weapons.
Gain 20 Followers.
Defeat Shamura.
Unlock all curses.
Fully Upgrade Cult.
Unlock all doctrines.
Catch 1 of every fish.
Defeat Heket.
Unlock a new fleece.
Cook a Follower meat meal.
Gain 10 Followers.
Sacrifice a Follower.
Salvation awaits the fallen soul.
Reignite the lighthouse.
Defeat Leshy.
Win a game of Knucklebones.
A new world awaits.
Gain 5 Followers.
Let the Word be known.
Defeat the first mini-boss.
The first devotee to the Cult of the Lamb.
A deal that cannot be undone.
No longer a servant, no less than a God.
Collect all Relics.
Get your Gold back from Midas.
Complete a row in Purgatory.
Unlock all lore.
Unlock all outfits.
Have 12 Disciples.
Completely Upgrade the Temple.
Hatch 5 eggs.