There is nothing to design here. We build a box with 1 entrance and a corridor of 5 cells. All zombies will walk along the corridor together. We take coffee in our left hand and start drinking, with our right hand we keep our sight on the corridor and press the button if we see movement. The main thing is that the hand does not go numb during the night.Again though, I do think that the stationary part is the big drawback. In my experience during blood moons, enemies will rotate where they try to attack from throughout the night. It would only have 90 degrees approximately of view, making it something you would need to design around.