Janah, Kaya's Shadow

When Janah, Kaya's Shadow enters the battlefield, target opponent reveals their hand.
You choose a nonland card from it with mana
value 4 or less. Exile that card until Janah leaves
the battlefield.
When Janah is put into exile from anywhere
other than the battlefield, you may put it onto
the battlefield. If you do, exile it at the beginning
of your next upkeep or if it would leave the battlefield.