This study examines the interplay between choice blindness and moral decision-making through the design and implementation of a decision-driven adventure game called Lost Civilization. Choice blindness, a phenomenon where individuals fail to detect changes in their decisions, was investigated within a controlled narrative environment featuring moral dilemmas in total, 56 participants (24 female, ages 18–35) engaged with the game, which subtly manipulated one of their moral decisions. The findings reveal that the majority (37) of participants did not detect the manipulation, underscoring the potential of games as tools for studying moral cognition and agency. Logistic regression analysis and machine learning models demonstrated significant correlations between undetected manipulations and participants’ gender as well as specific moral foundation scores based on Jonathan Haidt’s and Oliver Scott Curry’s dictionaries, suggesting deeper psychological underpinnings of decision-making processes. This research highlights the utility of video games in expanding the scope of choice blindness studies and advancing our understanding of ethical agency in interactive contexts.