Alternate Reality Games (ARGs) are being used increasingly in Higher Education to provide a stimulating context for student learning. By combining a narrative with puzzles that are solved by a community, both online and in the real world, they offer the opportunity to create problem-based learning experiences where students can work together to discover secrets and solve mysteries. Some players become highly engrossed in these games, expending large amounts of effort in solving challenges or creating artefacts. In the context of education, however, while high levels of engagement are seen in many students, it is certainly not universal. This paper draws on four case studies of the use of an ARG-based learning environment to examine what can be learned about motivation, and how this could be used to influence student engagement in learning. This paper first explores the literature on motivation with games and learning, and presents a model for understanding motivation with ARGs as a distinct genre. Then four cases studies are used to explore different ways in which motivation can be facilitated in educational ARGs (and activities that are inspired by ARGs). This includes two of games to support student induction, an online problem-solving course to teach Historical research skills, and the first charity ARG, presenting a comparative study from a related sector. Each of these cases will be described and the lessons learned with respect to motivation highlighted. Finally, the paper will explore and discuss overarching issues raised in the case studies. In particular: pros and cons of competition; appropriate levels of challenge for motivation; increasing participation levels and the niche ARG aesthetic; assessment; and ways of increasing learner autonomy. In all, this paper hopes to provide an insight into what can be learned about motivation from alternate reality games.