They had built a better barracks so now I can build hillmen.
Yeeesh. Hillmen are worthless, IMHO. All of the disadvantages, and none of the advantages of Eastern Infantry.

Bribed Armenan army and got two units then assaulted Artaxerta
I take it you snagged their Cataphract unit? It's what I do, if that's the case. Better to have the unit fight on your side than against....