The Captain of the Guard is a cultured person. They use the little free time they have for their alchemic experiments and their passion of music. Their Tower is their place of work, where they handle all the day to day appointments. It also functions as a place of power, where a few guards are always posted, ready to use the heavy balistae on unsuspecting foes.

Maybe the heroes are called into their office, to recieve payment, when an unsuspecting ambush has them fighting inside the tower from top to bottom? You decide!