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