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 Heket without taking damage.
Unlock all Follower Skins.
Beat Kallamar without taking damage.
Unlock all fleeces.
Beat Shamura without taking damage.
Unlock all tarot cards.
Reignite the lighthouse.
A deal that cannot be undone.
Sacrifice 10 Followers.
Catch 1 of every fish.
Beat Leshy without taking damage.
Defeat all opponents in Knucklebones.
Win a game of Knucklebones.
Defeat the One Who Waits.
Defeat Shamura.
Find all 5 locations.
Take confession.
Defeat Kallamar.
Have 666 gold coins.
Unlock all curses.
Gain 20 Followers.
Unlock a new fleece.
Unlock all weapons.
Unlock all doctrines.
Defeat Leshy.
Fully Upgrade Cult.
Defeat Heket.
Cook a Follower meat meal.
The first devotee to the Cult of the Lamb.
Gain 5 Followers.
Gain 10 Followers.
Sacrifice a Follower.
Defeat the first mini-boss.
A new world awaits.
Let the Word be known.
Salvation awaits the fallen soul.
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.