In this chapter, I explore the theory, design, and implementation of formal game-enhanced L2TL. The first part presents the concepts of pedagogical mediation and supplemental or wraparound materials. The second part presents three approaches that can be applied when evaluating and selecting vernacular games for L2 learning use: to consider its affordances, its CALL appropriateness, and learner-player preferences. The third part presents six frameworks for the design of pedagogical mediation: gaming literacies, game discourses and functions, game dynamics, narrativization, experiential learning, and bridging activities. The chapter concludes with a practical guide to game-enhanced L2 learning project design and implementation, including outlines of sample projects.