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