The aggressor’s pieces would be twice as many as the protectors. The word “hnefi” stands for the king of this game. Why the middle-square is standing out on the board is because that is the location of the king-piece, surrounded by his small army of protectors. The whole point of the game is that the king should be able to escape in order for the player who plays the protective side of the game to win, and if the king doesn’t make it out of harm’s way, the player on the aggressors’ side would win.