This supplement is to cover expenses that could not have been foreseen at the time of application, including recruiting costs and incentive costs. The study aims to assess the acceptability, usability, and efficacy of using state-of-the-art social media and game technology to increase HIV testing among adolescents and young adults (AYA) ages 13-24. Rates of HIV testing among AYA are low, resulting in high proportions of AYA who are unaware of their HIV infection. Since many AYA are highly engaged with social media and games, these technologies may hold the key to reaching this population. While previous behavior-change games have shown positive results by using the compelling nature of gameplay to make health education entertaining and shift attitudes towards disease prevention, this intervention proposes to incorporate a new innovation which changes the way video games are used to increase HIV testing and linkage to care. The intended result is a novel experience which plays like a game while prompting dialogue about HIV risk assessment, testing, and linkage to prevention in a manner that may be more acceptable to AYA compared to traditional public health messages. We have developed an AYA-informed game in which players can create characters like themselves, model different forms of dating and sex practices to learn the consequences in a simulated, non-health or life-threatening environment, and identify locations for HIV testing and prevention services. We seek to test the efficacy of this game and hypothesize that its use will result in increased HIV testing and lead to a reduction in risky behaviors among AYA at risk for HIV. In this Phase II application, our multidisciplinary team recruited AYA for iterative focus groups to confirm the acceptability of additional game enhancements. We then conducted pilot field testing of the game intervention among AYA (n=10) to ensure usability, acceptability and to conduct quality assurance testing. We now plan to conduct a randomized controlled trial to determine the efficacy of the intervention on HIV testing uptake. We will enroll 300 sexually active HIV negative AYA and randomize them to receive either the life-simulation game intervention or an app which contains HIV educational materials. We will compare self-reported HIV testing between the two study groups. Successful completion of these aims will demonstrate how this product may advance the effective implementation of an evidence-based behavioral intervention for increased HIV testing and linkage to preventive care among youth. Successful development of this core technology could also be revised to be applicable to other medical conditions.