Hello. Sometimes when we decide to attack someone, we select first the champions that can escort our units because they come first to our acropolis tab, and after we select the units,but  in this way, it is possible that we might choose fewer units of what the champion really can cover, so the game gives us a notification that we selected more champions that we really need. It is a good thing as if you ignore it, you will end up losing your champions in vain. As you may see in my screenshot, I ignore it, and I lost my cataphracts in vain, so trust me, you better not ignore it, and not ask to get rid of it🙂 The little shield most probably it is the sign that those units are veterans. We can have veterans by using orichalcum in Pantheos to make veterans our selected units, or we are getting them  for free, from our infirmary, because we used certain champions that give this ability. The veterans and the Elite units have more stats than the regular units. Regarding the Persian attacks, as a Persian specialist, I would advise you to try to get payouts from both offensive and offensive positions as the game might stop to give us  good payouts when we are focused only on one type of position. Plus, I would strongly advise you when you attack  the Persian positions, send  ONLY what units you can train with timber, bronze, and grain, and not units from denaries, definitely not acolyte units, and for sure NOT champions.🙂

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