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