Assasins, Templars, Monastic orders and of course Beelzebub
Paradox Interactive likes going into extreme detail with their grand strategy titles and the newest DLC for Crusader Kings II does just that. Lots of new features have been added for all those who like to take a more spiritual route to incest and fratricide. Monks and Mystics adds monastic orders, devil worship, secret societies, relics, treasures and other aspects of religion and faith to the base game.
In case you want to silently whisper Hail Satan to yourself while signing an assassination order for your wife who is also your aunt and possibly cousin, you can do so now at a discount. Crusader Kings II is 75 per cent off with Steam at the time of writing and the offer expires on 10 March 2017.