I know that mines stay on the board unless removed by a sapper. But wouldn't the game be better if they were removed when any piece encounters one? In other words, if a piece (other than a sapper) steps on a mine, the piece is removed AND the mine is also removed. This would make the game more challenging. Also, the way it is now, if you lose all your sappers and your opponent has his HQ surrounded, you can't win.