Suspense, a signature of riveting competitions, arises in part from the delicate balance between skill and chance. As spectators, we prize excellence and want highly skilled competitors to be rewarded for their efforts; however, we also love to root for an underdog. It is this tension between supremacy and uncertainty that makes sports so compelling. The outcomes of competitions and many other activities are determined by a blend of skill and luck. A variety of factors impact the relative importance of these two effects: rules and regulations, physical and biological considerations, and environmental factors. In this talk we will explore mathematical approaches to estimate the relative role of skill and chance based on win/loss records, and build on this understanding to suggest strategies for game designers to tune the skill-luck ratio in different games.