Crusader Kings II achievements

As the Anti-Christ/spawn of Satan, become Grandmaster of the Satanists.

Kill a character with the Immortal trait.

As a Tribal ruler, gain a title you have a claim on by duelling the holder.

Successfully slander 20 people with one character

Be King of Frisia and hold the Atlantic coast from Léon in Brittany to Jylland

Play as three consecutive generations of empresses

Play a game all the way through from 867 to 1453

Found a Legendary Bloodline while part of a Warrior Lodge.

Become Emperor of Francia as Carloman, brother of Charlemagne

Enforce peace for 6 or more vassals.

As a Muslim King or higher, become Grandmaster of the Assassins.

As a King or Emperor, have one of your domain Counties under the influence of a successful Rain Dance.