Here is the full list of all 30 Curse of the Dead Gods achievements.
Defeat Clovis Pardieux, Champion of Death
Become the new Champion of Death
Complete 10 different "Special Events"
Write all Bestiary entries with their complete sketches
Get 3 successful Parries in less than 2 seconds
Equip the three weapons slots with Cursed weapons
Unlock all Weapon Altars upgrades
Unlock 20 Blessings of the Dead Gods
Complete any exploration with 50 or more Constitution
Complete any exploration with 50 or more Dexterity
Make 10 Blood Offerings during a single exploration
Equip a hidden Champion weapon
Complete any exploration with 50 or more Perception
Defeat the Dark Avatar of the Eagle
Defeat the Dark Avatar of the Jaguar
Unlock 20 Forsaken Weapons
Defeat the Dark Avatar of the Serpent
Defeat Ratyapu, the Abomination
Lift the Final Curse
Defeat Litz & Nepac, the Cursed Twins
Defeat Malok paal, the Flesh Monstrosity
Write 5 Bestiary entries
Unlock 5 Forsaken Weapons
Defeat Xucat', the Witch
Defeat K'ax taca, High Lord of the Storm
Achieve a x10 "Greed Kill" series
Defeat Xak'olchir, the Blood Hunter
Start a "Special Event"
Unlock a Blessing of the Dead Gods
Complete the room of Trials