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