Somebody did the comparison, I think it takes three units of Hillmen to defeat one unit of EI. Maybe it was two units of EI. As far as the Onagers goes, it takes a while to get to the point of building Onagers. Then again, with the lousy infantry, one should focus on upgrading the archery range and stables instead of the barracks, so you will get there more quickly. If all you need is a first level barracks for EI, then don't waste your money going better. The extra experience that is gained (if I remember correctly) from a better barracks is not worth it to improve a lousy unit that you will want to use sparingly anyway. And once you get to your better cav, forget the infantry. And if dealing with chariots, if you can have Elephants, chariots are nothing. But if you must use infantry, you are better off with slingers and archers, with maybe some EI to ?protect? them from cav. One thing is sure, with Parthia you don't want to fight using a traditional battle line.
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