Bell of Summons
This what seems to be an ordinary silver bell when rung summons what looks very much like the Emperor.
Long ago this bell was in the possession of a powerful Vampire Prince during a ball held in the name of the legendary Toreador. Several times the bell would be rung during the Toreador ball and the Emperor came to the knees of the Vampire Prince waiting to do his bidding. Once the ball had ended the bell disappeared and the Prince eventually met his end.