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.
Unlock all Follower Skins.
No longer a servant, no less than a God.
Unlock all fleeces.
Beat Kallamar without taking damage.
Unlock all tarot cards.
Defeat all opponents in Knucklebones.
Beat Heket without taking damage.
Beat Leshy without taking damage.
Defeat the One Who Waits.
Defeat Shamura.
Beat Shamura without taking damage.
Sacrifice 10 Followers.
Find all 5 locations.
Defeat Kallamar.
Gain 20 Followers.
Unlock all curses.
Unlock all doctrines.
Unlock all weapons.
Fully Upgrade Cult.
Have 666 gold coins.
Take confession.
Defeat Heket.
Sacrifice a Follower.
Cook a Follower meat meal.
Salvation awaits the fallen soul.
Unlock a new fleece.
Catch 1 of every fish.
Gain 10 Followers.
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.
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.