zealous dagger
In this case -- using the Hussite Wars -- when I made peace with Bohemia, knowing Ill want to deal with them later I chose to take the middle of their country, of all places. Now this will obviously make their country nunfunctional, due to how controll works, rendering them wholly vulnerable for my future conquests, but just in genera ruining their country... And I didnt have a very big warscore, just like 20...
(Praha is me)
Now Bohemia is like, probably you can tell too doesnt exactly look very menacing anymore. Just because I could take a random place... (Okay, there were other things not exactly going for them too, not just me...)
snow herald
I got this when npc Lithuania was fighting Novgorod, it just took two provinces bordering me, which makes no sense and is an eye soar.