Mystery

If you search your library for a card that you
would then put into your hand, you may reveal
it, then exile it with a card from your hand and a
card from your graveyard all facedown instead.
When do you do, shuffle them, manifest one of
those cards, put one into your hand, and one into
your graveyard, each at random.
When Mystery is put into a graveyard from
anywhere, shuffle it into its owner's library.