Stone Librande discusses using paper simulations to understand the fundamental design principles of digital games. He instructs participants to select a digital game and remove its controller, sound, music and graphics to focus on its core gameplay. Participants are divided into groups and tasked with quickly prototyping the selected game using only pencils, index cards and dice. This allows designers to test how the game's aesthetics survive without technology. The process is intended to be fast, cheap and help designers understand existing games or keep them focused while developing new ones.