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 fleeces.
Beat Shamura without taking damage.
Unlock all tarot cards.
Unlock all Follower Skins.
Defeat the One Who Waits.
Defeat Shamura.
Defeat all opponents in Knucklebones.
Sacrifice 10 Followers.
Gain 20 Followers.
Find all 5 locations.
Have 666 gold coins.
Defeat Kallamar.
Beat Kallamar without taking damage.
Take confession.
Unlock all weapons.
Fully Upgrade Cult.
Defeat Heket.
Beat Heket without taking damage.
Unlock all doctrines.
Unlock all curses.
Catch 1 of every fish.
Gain 10 Followers.
Unlock a new fleece.
Sacrifice a Follower.
Reignite the lighthouse.
Cook a Follower meat meal.
Salvation awaits the fallen soul.
Defeat Leshy.
Beat Leshy without taking damage.
Gain 5 Followers.
Win a game of Knucklebones.
A new world awaits.
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.