In Japan, the equivalent of the ESRB is the Computer Entertainment Rating Organization (CERO), the industry outfit responsible for giving content ratings to every console game released in the country. CERO rates based on a scale of five letters: A (all ages), B (ages 12 and up), C (ages 15 and up), D (ages 17 and up), and Z (ages 18 and up only ). That “only” attached to the Z rating has been the source of consternation for many a gamer in Japan
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All about Japan’s Anti-Violence Game Rating System