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.
No longer a servant, no less than a God.
Beat Heket without taking damage.
Beat Kallamar without taking damage.
Beat Shamura without taking damage.
Unlock all Follower Skins.
Unlock all fleeces.
Defeat the One Who Waits.
Defeat Shamura.
Unlock all tarot cards.
Defeat all opponents in Knucklebones.
Defeat Kallamar.
Find all 5 locations.
Have 666 gold coins.
Sacrifice 10 Followers.
Beat Leshy without taking damage.
Unlock a new fleece.
Gain 20 Followers.
Reignite the lighthouse.
Catch 1 of every fish.
Cook a Follower meat meal.
Defeat Heket.
Win a game of Knucklebones.
Unlock all doctrines.
Unlock all curses.
Unlock all weapons.
Fully Upgrade Cult.
Take confession.
Sacrifice a Follower.
Gain 10 Followers.
Salvation awaits the fallen soul.
Defeat Leshy.
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.
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.