Got my revenge on that mofo. Maharaja Nagdeo, "the wise" I think it was.
So this guy is an adventurer who comes along and get his own kingdom by attacking Chandana, my neighbour (who I intended to invade anyway). Big deal you might think, divided they fall. Well yeah, but the 20.000 guys Nagdeo brought with him stuck around, and he decide he wants a piece of MY land. Since I'm very spread out it takes MONTHS to assemble my armies, and by then he assaulted the wargoal and then some, forcing me to peace out despite being very much able to kick his sorry ass. (news: the next patch will prevent that, yay!)
I brood my revenge while Nagdeo continues holy warring like a madman, cutting himself pieces out of the neighbouring hindus and even out of my neighbours the Zandids (who took the place of the Saffarids). They get too greedy however, and expend their troops. As they attack the Zandids again, I strike. Well, I issue a declaration of war and take a year to assemble the friggin levies.
Then I lose everything in a tactical mistake. Out of 24 thousand men, three thousand come home. It's a disaster.
But Nagdeo now concentrate on the Zandid, sure of his victory.
I reassemble my armies, and another twenty thousand, led by veteran generals and a fresh retinue of 4500 horsemen. Time to pay.
This time I manoeuver carefully. Nagdeo wins against the Zandids, but his armies are thinned by the wars, and I catch his 16.000, led by the hindu holy order, with my 21.000. Two third of his army are killed, to a seventh of mine.
I split my army in two, one chasing the remnants around and killing more than its share of filthy heathens, the other, with the retinue, siege the holdings. The Zandids, with a replenished levy, declare a war of reconquest. In the end, I carpet siege, and I win. The Zandid reconquer their capital too (although they ultimately decide to take the saffarids' old capital after all). And Nagdeo is reduced to a duchy and a half, with half of it immediately instantly rebelling.
And with a sixth kingdom title, I still can't create an empire because I'm spread out over three de jure empires. Damnit.