The Staff of Osiris

The Staff of Osiris, is, like the Mask of Anubis and the Cup of Ankh, a mystical Egyptian object. It has apperantly dangerous powers, since even Harriet was shocked when she found a scroll with it draw on it and said it was "far too dangerous and risky" to use it.

It is highly possible the artifacts hidden by the descendants of Joy, Jerome, Alfie and Patricia, are able to be fit together to create the Staff, possibly as part of Robert's plan if he were to wake up evil.