Depression and anxiety are the most frequently diagnosed mental health problems, leading to devastating long term outcomes that affect a huge proportion of children and adolescents across the globe. Effective prevention programs that show more than a small effect size and that do not stigmatize, condescend to, and bore children, are urgently needed. Our research program focuses on developing evidence-based games that promote emotional resilience through training skills while youth are immersed in games they love to play. We prioritize design and art, integrate developmental science and principles of behavioral change, and systematically test our gaming interventions with large-scale randomized controlled trials. In this talk I will: (a) describe the cross-disciplinary framework we use to develop mobile and virtual reality games that integrate biofeedback and evidence-based game mechanics, (b) present data from a series of randomized controlled trials that evaluate games that use biofeedback at their core (e.g., EEG neurofeedback, heart rate); and (c) introduce a roadmap to the next five years of programmatic studies in biofeedback games, emphasizing how our design and research methodology can help establish a validated toolbox of mechanics relevant to a wide range of intervention and learning domains.