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.
Beat Shamura without taking damage.
Beat Kallamar without taking damage.
Beat Heket without taking damage.
Sacrifice 10 Followers.
Unlock all fleeces.
Beat Leshy without taking damage.
Unlock all Follower Skins.
Unlock all tarot cards.
Catch 1 of every fish.
Defeat the One Who Waits.
Defeat all opponents in Knucklebones.
Defeat Shamura.
Find all 5 locations.
Defeat Kallamar.
Unlock a new fleece.
Unlock all weapons.
Unlock all doctrines.
Unlock all curses.
Take confession.
Have 666 gold coins.
Reignite the lighthouse.
Fully Upgrade Cult.
Defeat Heket.
Gain 20 Followers.
Cook a Follower meat meal.
Sacrifice a Follower.
Gain 10 Followers.
Defeat Leshy.
Salvation awaits the fallen soul.
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.
Complete a row in Purgatory.
Collect all Relics.
Get your Gold back from Midas.
Unlock all outfits.
Unlock all lore.
Completely Upgrade the Temple.
Have 12 Disciples.
Hatch 5 eggs.