On The Case consists of four puzzles as well as a meta. Each puzzle solves to a characteristic of some of the suspects, which the player then connects to the case on a big corkboard by cutting and using yarn. If the puzzles are all solved correctly, the yarn should cross over three different suspects; when the initials for each of the suspects are put together, the mastermind is revealed!

This puzzle had a couple of hiccups in development. Namely, we were challenged with ensuring that the yarn would always line itself up correctly; we spent a lot of time iterating on where each of the suspect's names would be, as well as where the case cards the suspects needed to connect to would be. Eventually, we found a layout that worked well on paper, but the real test would come once we had the board constructed and in front of us.