In order to win in Tower Duel mode you will have to beat the clock which is set at six minutes. To have any chance of doing this it is important that you do not linger too long in any of the categories. If you come across a question you have absolutely no idea what the answer is it is more beneficial to move on to the next question instead of wasting precious seconds. The objective of Tower Duel mode is not to get a perfect score but to earn more than your opponent within the time limit.