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