This paper extends an established framework for analysing abstraction and realism in serious games by introducing a seventh dimension that accounts for how cultural meaning is constructed, represented and interpreted within game environments. While the existing model describes the pedagogical implications of fidelity across visuals, audio, mechanics and interface, rules, narrative and feedback, it provides limited guidance for understanding how domain-specific values, practices and material cultures are encoded into playable experiences. To address this gap, the proposed Domain Culture System draws on anthropological theory and intercultural game studies to articulate how cultural ideology, practice and material can be conveyed at varying levels of abstraction and realism. The resulting multidimensional spectrum provides designers and researchers with a structured way to examine how cultural logics shape player interpretation, engagement and learning, alongside other factors that influence the realism of serious games.