A [MultiplayerPeer] which is always connected and acts as a server.
This is the default [member MultiplayerAPI.multiplayer_peer] for the [member Node.multiplayer]. It mimics the behavior of a server with no peers connected.
This means that the [SceneTree] will act as the multiplayer authority by default. Calls to [method MultiplayerAPI.is_server] will return [code]true[/code], and calls to [method MultiplayerAPI.get_unique_id] will return [constant MultiplayerPeer.TARGET_PEER_SERVER].