The Legends of the Dead Add-on for Crusader Kings III has 11 achievements.
Contract, and recover from, the Bubonic Plague
Reach the maximum level of Legitimacy
Travel to a safe holding while your Capital is infected by a Epidemic
As a Scottish character, complete a Legend claiming your descent from Ancient Egypt
Manage to make your Legend Protagonist a Saint
Successfully claim your Liege's title while having a higher Legitimacy Level than them
Have an infected Barony at the maximum Epidemic Resistance
Complete a Legend
Host a Funeral for your Legend Protagonist
As a Count, complete a Mythical Legend
Complete your ancestor's Legend after their death