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