Multiplayer without your own server: rooms and voice

What the player sees

• Rooms of the games that play online: public, or private with an invite code.
• "Create a room": name, 2, 4 or 8 players and the game's own room settings.
• Members with host, "Ready" and offline marks, room chat and removing a member.
• Voice chat: mic off, push-to-talk on V or open mic, mute and volume of every member, who is speaking.
• "Play" of the host takes every device of the room into the game.

How it works

• The lobby owns the room and its session; games never create or join rooms themselves.
• A game plays online by registering in the lobby; then "With friends" appears next to its "Play".
• Late joiners can enter a running game when the game allows it. The voxel sandbox is the reference.

For developers

Rooms work through client.multiplayer and RealtimeSession (@idosgames/core/realtime); a game connects through ctx.multiplayer.

// In the game module's setup(): the game plays online through the lobby rooms
ctx.multiplayer.registerGame({
  mode: 'my-game',
  topology: 'Host',
  chatMode: 'ServerRelay', // the lobby's room chat
  maxPlayers: 4,
  joinInProgress: true,
  // On every member's device once the host pressed "Play"
  start: async (room) => startOnline(room.session, { host: room.isHost, leave: room.leave }),
})

• Leave with room.leave(): the lobby owns the room.
• Show "Play with friends" only while the multiplayer feature is available: without it the game stays single-player.

Every field is described in the multiplayer-realtime skill, served by the SDK MCP server.