The Roman army isn’t large but it is tough. The General has 2 gold chevrons, gold sword & shield. The Aquila Legions have 2 silver chevrons, silver sword & shield, while the other 6 Legions have 1 silver chevron, silver sword & shield. The rest of the army is similarly equipped.
The Parthian army is larger but not so tough. The General has 1 gold chevron, gold sword & shield. The Kataphractoi have 3 bronze chevrons, silver sword & bronze shield. They were NOT allowed to use their bows & they act as ordinary cavalry. The rest of the army has a mix of 1-3 silver chevrons, sword & shields.