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.
Catch 1 of every fish.
No longer a servant, no less than a God.
Reignite the lighthouse.
Unlock all fleeces.
Unlock all Follower Skins.
Unlock all tarot cards.
Sacrifice 10 Followers.
A deal that cannot be undone.
Beat Shamura without taking damage.
Beat Kallamar without taking damage.
Beat Heket without taking damage.
Take confession.
Defeat Leshy.
Beat Leshy without taking damage.
Defeat the One Who Waits.
Gain 20 Followers.
Defeat all opponents in Knucklebones.
Defeat Shamura.
Cook a Follower meat meal.
Find all 5 locations.
Unlock a new fleece.
Defeat Kallamar.
Unlock all curses.
Have 666 gold coins.
Unlock all doctrines.
Unlock all weapons.
Defeat the first mini-boss.
Fully Upgrade Cult.
Win a game of Knucklebones.
The first devotee to the Cult of the Lamb.
Gain 5 Followers.
Gain 10 Followers.
Defeat Heket.
A new world awaits.
Sacrifice a Follower.
Salvation awaits the fallen soul.
Let the Word be known.
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.