The player with Ashigaru in his team always plays second for the opening round of the fight. If both players have Ashigaru in their teams, the order of play is random.
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In fact its an advantage when you play second in the opening round, that way you play second in the third round, wich is a very good thing since you then know what card your opponent will play in the last round.....you have the choise of two card (in the third round) and your opponent has already played his card......
Hope you understand it....its past midnight here and my brains aren't working properly (alcohol kills braincells).
Oh and by the way, the one to play first is always the one with the most stars (combined level of all cards)......if two players have the same amount of stars its random of course.