If you know a way to find out which heroes are visiting an opponent's tavern in HoMM, please share it.

There is a method, very simple in essence. It's a method of elimination. I know how many heroes there are in total. I know how many computer-controlled players are on the map. I subtract twice the second number from the first. Then I start digging up all possible heroes. As soon as their number equals the calculated number, I stop and look at the heroes that haven't been dug up. They are the ones sitting in the taverns of the computer-controlled players. The process is quite laborious, but it doesn't involve directly accessing the save file. Although, of course, that would be much easier.