I have changed from the Umma to the Romans and I think that the scenario is a bit boring for the Romans. After seeing the screenies etc i thought i would get my ass kicked but...
I have lost ONE city so far

. Im playing on Monarch and there is NO challange. The first turns were pretty hard and i thought i would loose my eastern empire, but after loosing the most north-eastern city the persian advance was halted by my Theodora army. I haven beaten 2 armys (and one of these was VERY big) easily and i have captured the first persian city (in the south).
The Avars aren´t a problem either and I´m currently making a small crusade against em. They are just too few and too weak.
My North-Eastern-Uber-Army has captured 4 citys(2 of these VPLs), beaten 3 small armys and im just burning everything one my way. I have just captued the persian archery wonder but im cant hold any of these citys, therefore im razing them. Soon there capital will fall.
The two aravs are killing each other and I havent seen the Umma yet.
You will have to do sth about the armys since AI suchs with armys. Maybe they should be deleted and the units would form a stock of death army. Further the Avars could need a bit help since they are pretty ridiculous. I want to get my ass kicked as Rome

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BTW: There is a bugged sound when you speaman militia gets attacked and the death animation of the arabian horseman multi-unit is strange too.