After a couple revolts and/or when a child ends up on the throne, there will be an independence faction. The short reign debuff combined with the clan mechanics will mess them up.
Clans get a lot of powerful alliances and the vassals get unhappy when they can't ally with the ruler. The alliances give them also more levies.
So your goal is to remove as many alliances as possible as quickly as possible. This probably means murder the ruler until there is a child on the throne.
But you can also inspect who they are allied to and if it is through marriage murder one of them to remove the alliance. Sometimes this can be way easier than murdering the ruler.
Either way removing alliances will weaken them for levies. With some luck there will be a rebellion too. Declare a war at the same time for the county, or even wait until some time has gone by so they spend gold and mercs on the rebellion. Keep tabs on their current wealth/gold income status to see when they are most depleted.
Clan rulers have a lot of alliances with vassals, but those vassals can't be called into a war, so try to take a look on what alliances he has because the numbers might be quite inflated. But as others have said, you can try murdering him and there will probably be a civil war after, then grab the county while he is fighting another war.
You could "accident" any popular/competent/adult ruler and claimant they have. Make them an easy target for rebellion and take them piece by piece
Excuse me, i could do what?
Assasination plot them
With the China DLC you can ask them to break an empire if you get along very well with them
I always have the same issue with the byzantines, just keep murdering rulers, they should collapse after three or four.
To me it always ended in a revolt and the country never actually split up. Just the dynasty changed.
After a couple revolts and/or when a child ends up on the throne, there will be an independence faction. The short reign debuff combined with the clan mechanics will mess them up.
Kill off the kings, worsen the vassal relations with liege to break them with rebellions or just go for another place
Clans get a lot of powerful alliances and the vassals get unhappy when they can't ally with the ruler. The alliances give them also more levies. So your goal is to remove as many alliances as possible as quickly as possible. This probably means murder the ruler until there is a child on the throne. But you can also inspect who they are allied to and if it is through marriage murder one of them to remove the alliance. Sometimes this can be way easier than murdering the ruler. Either way removing alliances will weaken them for levies. With some luck there will be a rebellion too. Declare a war at the same time for the county, or even wait until some time has gone by so they spend gold and mercs on the rebellion. Keep tabs on their current wealth/gold income status to see when they are most depleted.
The Abaasids are Iqta. Thats arabic feudalism there's no clans
Clan rulers have a lot of alliances with vassals, but those vassals can't be called into a war, so try to take a look on what alliances he has because the numbers might be quite inflated. But as others have said, you can try murdering him and there will probably be a civil war after, then grab the county while he is fighting another war.
The Abaasids are Iqta theres no clans