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