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.
Unlock all Follower Skins.
No longer a servant, no less than a God.
Defeat the One Who Waits.
Beat Shamura without taking damage.
Beat Kallamar without taking damage.
Unlock all fleeces.
Unlock all tarot cards.
Defeat Shamura.
Defeat all opponents in Knucklebones.
Sacrifice 10 Followers.
Find all 5 locations.
Defeat Kallamar.
Beat Heket without taking damage.
Unlock all curses.
Take confession.
Gain 20 Followers.
Defeat Heket.
Unlock all weapons.
Unlock all doctrines.
Fully Upgrade Cult.
Win a game of Knucklebones.
Beat Leshy without taking damage.
Cook a Follower meat meal.
Unlock a new fleece.
Catch 1 of every fish.
Have 666 gold coins.
Gain 10 Followers.
Sacrifice a Follower.
Salvation awaits the fallen soul.
Reignite the lighthouse.
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.
Complete a row in Purgatory.
Get your Gold back from Midas.
Completely Upgrade the Temple.
Unlock all outfits.
Unlock all lore.
Have 12 Disciples.
Hatch 5 eggs.