The The Reaper's Due Add-on for Crusader Kings II has 12 achievements.
Survive the End Times.
Recover from the Black Death.
Die from the Black Death.
From Seclusion, kick someone out who had the plague.
Become One-Eyed, One-Legged and One-Handed.
Have elephants trample the Pope/Caliph.
From Seclusion, kick someone out who did not have the plague.
Contract three symptoms.
Build a Hospital.
Go into Seclusion.
Kill a character with the Immortal trait.
Become immortal.