Planar Gateway

You may reveal, exile, and mill cards in your
hand as if they were on top of your library.
You may reveal, exile, and discard cards on top
of your library as if they were cards in your hand.
(These effects do not change the total number of cards affected. For instance, if you were to reveal your hand
while having five cards in hand, you must reveal five
cards in any combination of cards from your hand and
the top of your library.)