so that mean that if i am holding the title of king of italy and sicily, and for some error in succession, i lose the king title of Sicily it wont stay as a vassal the new king of Sicily but it will become a independent realm?
If i manage to become emperor, then by doing the antipope trick you should always be able take the papacy that way?
I have noticed that the normal fabricate claim does have 0% chance to succeed on the papacy lands, is that normal?
That error in succession is called gavelkind.
I think that's only if you have a member of your dynasty be the antipope. Imma gonna try this and get back to you with that.
No, that's not normal. You should be able to fabricate claims on Rome, Orvietto, etc.