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