In public spaces, communication among people with diverse values not only causes friction but also makes it hard to build relationships that bridge those differences. Simply expressing opinions is not enough to overcome divisions. To address this, we designed and implemented “Public Quest,” a communication game that frames a three-stage process within an RPG theme: (1) creative opinion expression through word games, (2) collaborative reconstruction of opinions via party formation, and (3) relationship building through face-to-face “Encounter” events. Through an exploration study, we observed that word games encouraged diverse expression. The “Name the Party” process led to the acceptance of a balanced range of opinions, while the “Encounter” event fosters positive dialogues and connections across differing views. This framing of communication as a shared quest supports not just creative expression, but also constructive engagement and relationship building in public spaces.