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