I saw this bug in an online game against Vigo.
As for the skeleton, I don't know. There was no duplication there. There were only skeletons in the garrison. Mike, Dust, and Alessandro could see it better from their side, so let them tell you.
It's not when 2 heroes run around the map.
It's when the hero's coordinates are one thing in the hero's structure, and another in the map's structure.
Let's say if one "copy" of the hero leaves the Castle, the second one inside may be visible or not.
If the one that left is dismissed, sometimes you can pull another one out of the Castle later. And sometimes you can't.
Sometimes the Castle also turns gray. And sometimes it doesn't.
As I said, there is a very wide range of manifestations.
In fact, the cure is based on forcibly overwriting all the "shadows" in the game save with zeros. Then, after loading, you need to move the heroes around so that their shadows are restored.
It's harder with the computer - a grayed-out Castle leads to a crash when building or buying a hero. And rolling back doesn't always help; the computer may not show symptoms for several turns after the duplication.
Here, you need to load the save into a hotseat game with 3 players, somehow reset the computer's money so that it can't build anything, pass the turn to the red player, save, and then load it over the network.
In TE, resetting the money is simple - you take and immediately give back credits so that the interest consumes all the savings. At the end, you also take out a maximum credit so that the computer can rest from construction work for a week. Of course, all heroes are dismissed at the same time.
In SoD, you can transfer money to another computer through the market, but there is often no market. And then there are big problems. At the tournament in Alaska on the Lite version (where the bank is disabled), we had such a situation in one of the matches. We had to do a trick - load the game online with three players, and the third player simply skipped the computer's turns.