As the interactive entertainment industry matures, a better understanding of what makes software entertaining is needed. A natural starting point is the application of traditional Human-Computer Interaction (HCI) tools to interactive entertainment software. HCI tools include cognitive models that researchers have used to model users’ thought processes and evaluate interface design. This paper users a simple cognitive model to investigate the relationship between the complexity of an interaction and the entertainment experienced by the user. We design a simple computer game, create a normative model for how a user plays this game, and build several variations of this game such that normative models of these variants differed across two factors: pace and complexity. User studies conducted on these variations allow comparison with these factors to user performance and self-reported user enjoyment. Users ingame enjoyment was found to be related to both the subject’s performance and th...