Educational computer games may improve learning experiences and learning outcomes. However, many off-the-shelf games still fail at smoothly integrating learning content into gameplay mechanisms. In addition, they do make an effort at adapting educational content to individual learners. Learner models and adaptivity, as applied by Intelligent Tutoring Systems (ITSs), address this problem. A solution to the integration dilemma would ideally be found at the software architecture level. Assuming the perspective of the software engineer, we review published game-based ITS architectures. The most promising approaches are partially integrated architectures, which replace sub-systems of Clancey’s (1984) classic ITS architecture with corresponding game elements. In order to provide a reference to developers, we follow up on these ideas and propose a unifying game-based ITS architecture based on genre studies of computer role-playing games.