i started an abbasid campaign as my first try at SSHIP (played SS before tho), difficulty is vh/vh. i renamed many of my settlements to nonhistorically-accurate names (usually either fantastical names or named after my faction leaders or other random stuff). currently i'm in a coldwar with the fatamids who are about tied with me for strongest faction. at the start of the campaign, the seljuqs refused to accept a ceasefire despite numerous offers of money, so i spent the first 35ish turns not expanding at all and just fighting the forces the seljuqs kept sending at me (that's pretty much all they did, was send stack after stack at me).
after the initial period of fighting to stay alive i was able to defeat and route a full seljuq stack which i thought (correctly) was the last large army they had at that time (had much of their territory scouted). also by this time i had the assassins' guild headquarters in one of my settlements too, and was assassinating their family members fairly consistently. having defeated their full stack, i conquered a large city (might've been metropolis) of theirs, and then began taking their settlements one by one. i also secured an alliance with the fatamids at this point that held up for almost 100 turns more. shortly after i also secured an alliance with georgia.
after fighting the seljuqs for awhile and taking all but their four northeasternmost settlements, my campaign of assassinations paid off as one turn i assassinated another of their faction leaders, afterwhich the message popped up that the seljuq faction was destroyed, and their last 4 settlements turned rebel. i mopped up, taking the rest of that area, then shortly after that the fatamids attacked the georgians and i decided to stay allied with the fatamids, and promptly invaded georgia. after some years i wiped them out too (the fatamids agreed to a ceasefire with them after taking only one of their settlements for some reason). then i finished off the zengids, who had only their capital left after much aggression by the crusader states, fatamids, georgians, and two crusades being called against them in a row. around this time i also allied with the cumans, and then shortly after that the fatamids betrayed me by sieging one of my settlements. i paid them a ridiculous amount of money to get them to agree to a ceasefire.
the fatamids have 6~ stacks near our border just chilling, so now i'm just building up my settlements while assassinating every fatamid family member i find, and paying them off a little bit each turn to stop them from attacking me. gonna just build my economy while i prepare for the mongols, who come soon.