  Existing metaverse systems lack rich relation types between entities and
events. The challenge is that there is no portable framework to introduce rich
concepts, relations, events into the metaverse. This paper introduces a new
metaverse framework, MetaOnce. This framework proposes to build multi-scene
graphs. This framework not only describes rich relations in a single scene but
also combines multiple scene graphs into a complete graph for more
comprehensive analysis and inference. Prior social network systems mainly
describe friend relations. They ignore the effect of entity-relation-event
games on the metaverse system and existing rule constraints. We propose a rule
controller and impose constraints on the relations that allow the framework to
behave in a compliant manner. We build a metaverse system to test the features
of the framework, and experimental results show that our framework can build a
multi-scene metaverse with memory and rule constraints.
