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.
Defeat the One Who Waits.
Unlock all tarot cards.
Beat Shamura without taking damage.
Beat Heket without taking damage.
Sacrifice 10 Followers.
Defeat Shamura.
Defeat all opponents in Knucklebones.
Defeat Kallamar.
Beat Kallamar without taking damage.
Find all 5 locations.
Gain 20 Followers.
Cook a Follower meat meal.
Take confession.
Have 666 gold coins.
Unlock all curses.
Defeat Heket.
Fully Upgrade Cult.
Unlock all weapons.
Catch 1 of every fish.
Beat Leshy without taking damage.
Unlock all doctrines.
Unlock a new fleece.
Sacrifice a Follower.
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.
Unlock all Follower Skins.
Unlock all fleeces.
No longer a servant, no less than a God.
Collect all Relics.
Get your Gold back from Midas.
Complete a row in Purgatory.
Have 12 Disciples.
Unlock all outfits.
Hatch 5 eggs.
Unlock all lore.
Completely Upgrade the Temple.