Question about normal attack calculation?

Hi guys.
I saw some calculation about normal attack I mean attack/defence, so I have two question.
First if I use two blue hero for example, their attack would be added together then divide per defence right? So is that happen for each tile?
I mean two same colour hero needs at least two tile to attack, so when I use rainbow team each tile has attack/defence separately.
So there is no difference between using two hero same colour or one hero right?
I used to think when I use rainbow team just attack is for one hero but when I use two hero the attack would be 700+800 for example. But if it relates to 1 tile it does not have any difference.
Expert guys help me out please

I was going to point you here but seems you already found this. So I’ll just close it.