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