Longitudinal studies investigating the relationship of aggression and violent video games are still scarce. Most of the previous studies focused on children or younger adolescents and relied on convenience samples. This paper presents data from a 1-year longitudinal study of N = 276 video game players aged 14 to 21 drawn from a representative sample of German gamers. We tested both whether the use of violent games predicts physical aggression (i.e., the socialization hypothesis) and whether physical aggression predicts the subsequent use of violent games (i.e., the selection hypothesis). The results support the selection hypotheses for the group of adolescents aged 14 to 17. For the group of young adults (18-21), we found no evidence for both the socialization and the selection hypothesis. Our findings suggest that the use of violent video games is not a substantial predictor of physical aggression, at least in the later phases of adolescence and early adulthood. The differences we found between the age groups show that age plays an important role in the relationship of aggression and violent video games and that research in this area can benefit from a more individualistic perspective that takes into account both intraindividual developmental change and interindividual differences between players.