LiverDefense: Using a Tower Defense Game as a Customisable Research Tool

In this paper, we present LiverDefense - an educational Tower Defense game illustrating the basic functions of the human liver. LiverDefense serves as an easy-to-use evaluation tool for psychological game-related research since it can be customised with regard to its degree of difficulty. Furthermore, Likert scale questionnaires can be displayed throughout the game and relevant game events can be logged. All customisation is performed via human-readable XML files, abolishing the need for programming proficiency. LiverDefense has been successfully used in a user study focused on exploring the effect of perceived control over gameplay on players' emotions. We report on the analysis of this study with regard to enjoyment and frustration and the resulting insights on LiverDefense's usefulness as a customisable research tool.