private void ReceiveObservingEntitiesRequest(byte[] body, ulong senderId)
        {
            Log.Trace("Receiving Observing Entities Request",
                      "ReceiveObservingEntitiesRequest");

            // nothing to read, but doing this anyway to test
            ObservingEntitiesRequest request = ObservingEntitiesRequest.FromBytes(body);

            // Convert them to just observing form
            ObservingEntitiesResponse response = new ObservingEntitiesResponse()
            {
                ObservingEntities = Session.Manager.Revealed.ObservingEntitiesList()
            };

            response.SendToPlayer(senderId);
        }