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