MOFA: Multiplayer Omnipresent Fighting Arena

As Mixed Reality (MR) head-mounted displays (HMDs) become more widely used, the context of collocated MR gaming is shifting from controlled, private environments to spontaneous, public settings in-the-wild. This shift transforms everyday locations into potential gaming stages, blurring the line between designated play areas and the public sphere. We term this phenomenon Spontaneous Collocated Mixed Reality (SCMR). This transformation necessitates game designs that accommodate both HMD wearers ("Wizards") and non-HMD wearers ("Muggles"). To explore the design space of synchronous social bodily interplay in SCMR, we developed the Multiplayer Omnipresent Fighting Arena (MOFA) framework. This framework leverages device asymmetry and role diversification to actively engage all participants. Using this framework, we created five game prototypes—"The Duel", "The Dragon", "The Ghost", "The Training", and "The Duck". These games, inspired by scenarios from fantastic fiction such as Harry Potter, Game of Thrones, and Ghostbusters, demonstrate that strategically involving "Muggles" enhances social engagement and acceptance. This helps us to speculate a shared mixed reality future that is more inclusive and entertaining in a ubiquitous and spontaneous manner.