 Move 6: This time, the proponent is not restricted by the   Last Duty First SR1i rule.  Since his repetition rank is \(\rank{2}\), he is allowed to answer a second time to the opponent’s challenge made at move 3. And since O played the elementary statement \(\Pa\) at move 5, P is able to choose it and play it at move 6. The opponent has no other possible move and the proponent wins this play.