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