Great guide. That's what I did in my Baktria game too - blitzing to the south, leaving everybody else alone. To prevent AS from overrunning me while my economy was still recovering I put some small garrisons of two phalanx units plus one archer on the river crossings south of Antiocheia-Margiane (never got attacked there in my campaign so far, but it feels safer and is a backup for a potential Pahlavan betrayal) and inbetween Alexandreia-Ariana and Prophthasia. That will keep the AS out, although it can get tough when they send some elite phalangites. I never got attacked from the north probably because Pahlava conquered Marakanda, but the AS keeps a fullstack around in Alexandria-Eschate that prevents both the Saka and Pahlava to finish them off in that region and probably helped me to keep up the peace with them for the last decades.
After securing my Western border I went for Kophen and built up mines in all the other towns until cashflow allowed me to conquer the remaining AS holdings to the south. After doing that, I went straight for India. I wanted to push AS further west after the succesful conquest at that point in the game but got attacked by the Saba who - of course - were crushed. With the help of the almighty toogle_fow I saw that the situation for AS had worsened and that next to an insanely active and succesful Carthage (they captured Rome and drove the Romans out of Italy and are now reconquering Spain after being completely wiped out there) the Ptolies were on the verge to become a large threat so I sent a expeditionary force to the Arabian peninsula to eliminate that and "aid" AS in keeping the Ptolies at bay. So far there have been some interesting battles including several naval invasions to capture and recapture Salamis and heavy skirmishes that ultimately led to the AS losing Antiocheia which is why I think they need help - I don't want to siege a Ptolie-Persepolis. Unfortunately I can't establish any client kingdoms (atleast with no recruitable governors) on my way to Egypt so that it probably will take a while - hopefully the AS will still be in the game by then.
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