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