Rhandine, Reverser of Time

Whenever Rhandine attacks, for each player
choose a permanent that player controls and
return it to its owner's hand. Then each
opponent chooses a card at random from their
hand and places it on top of their library.
{2}{ut}, Discard a card: Exile the bottom card
of target player's library. You may cast cards
exiled this way as long as they remain exiled.
(You may spend mana as if it were any color to
cast spells exiled this way.)