When a battle is happening between players, the other players who are not in the battle continue as normal. They skip the dice roll of the players who are battling. As soon as those who are battling are done they re-enter the normal Game Rounds with everyone else.
The above rule is overruled if there are 3 players or less in the game. If there are only 3 players or less in the game then each player in the battle and out of it must wait for their own Game Turn before they can attack/play. The same applies when a player is in the Market. There can be multiple battles at once. But no one can be in more than one battle at the same time. If you are the only player outside of a battle or the Market, you must wait 15 seconds between each turn.