On its three year anniversary, Paradox has made Crusader Kings 2 free to play (for a bit) through Steam. Until 23 February, you can download and play the medieval cousin-stabbing simulator for no money at all.
After 23 February it will vanish from your library, like a traitorous courtier fleeing from your wrath. Unless you buy it during that time, obviously. Then it’ll stick around like a contented mercenary.
In a cunning act of temptation, the game is 75% off at the moment. Some of the many, many DLC add-ons are on sale too. There’s even a complete collection available with every Crusader Kings 2 thing in it, reduced to $40.00 from $160.00.
I’ve not played every single add-on, but can recommend The Old Gods (which adds nutty Viking stuff) and Sons of Abraham (in which you can have a devil child.)
For those tempted to dive in to Crusader Kings 2 during this free period, try not to be too overwhelmed. It might look like you need to know all the medieval terms for royal succession, but that’s not strictly necessary. The game is very hard to “lose,” and a lot of the fun can come from just messing about and dealing with the consequences.