These are my two possible ways they will make the avatar system in Rome 2.
This is my speculation and my speculation alone.
Theory 1
You enter Avatar creation. You pick you faction. Create your avatar with the face and armor models of that faction. Color your flag or standard, pick a symbol only to that faction.
Then Choose your armies colors, and fight on the campaign map from where your faction starts normally. You can unlock traits that are universal and armor, along with units that are only specific to your faction. you can always add mercenary units from different factions.
Theory 2
You enter Avatar creation. Create your avatar, you can pick from all faction dress and face models. Choose your standard color and symbol. You can use any from any faction.
Choose your armies colors and you can either choose or be set randomly where you start on the conquest map. You can unlock traits witch are still universal, and units and armor.
You can use units from any faction plus mercenaries. Basically allowing you to mix all sorts of unit types from all different factions.
Witch is the best? Or do you have something better?











