We present a new toolset named MUN (Metaverse Unity Networking) based on AI algorithms for creating multiplayer VR environments, developed on the basis of user-centered design research. It includes a Unity asset enabling creation and configuration of the multiplayer mode in a VR setup, supplemented with 1) a recommendation engine for optimal programming methods, with error detection in application source code, 2) a user behavior analytics system in multiplayer mode, enhancing realism in avatar and NPC actions using a motion atlas and motion recognition. Developed using Python 3.9,. NET, and Unity v. 2021, it was validated by Unity developers through three rounds of usability tests (N=64).