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 Leshy without taking damage.
Defeat the One Who Waits.
Sacrifice 10 Followers.
Unlock all Follower Skins.
Unlock all fleeces.
Unlock all tarot cards.
Unlock all weapons.
Unlock all doctrines.
Unlock all curses.
Fully Upgrade Cult.
Defeat Shamura.
Beat Shamura without taking damage.
Defeat all opponents in Knucklebones.
Unlock a new fleece.
Catch 1 of every fish.
Take confession.
Find all 5 locations.
Defeat Kallamar.
Beat Kallamar without taking damage.
Salvation awaits the fallen soul.
Gain 20 Followers.
Cook a Follower meat meal.
Sacrifice a Follower.
Reignite the lighthouse.
Win a game of Knucklebones.
Defeat Heket.
Beat Heket without taking damage.
Gain 10 Followers.
Defeat Leshy.
A new world awaits.
Gain 5 Followers.
Have 666 gold coins.
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.
Complete a row in Purgatory.
Get your Gold back from Midas.
Unlock all lore.
Unlock all outfits.
Have 12 Disciples.
Completely Upgrade the Temple.
Hatch 5 eggs.