Rowena, Havenfire

0: Until the beginning of your next upkeep, cards in all zones of play lose their text if it contains one or more instances of the word "must".
X: Exile X cards you own from anywhere. Target permanent with converted mana cost equal to X gains hexproof until the beginning of your next upkeep.
-20: You get an emblem with "Players may cast spells from exile," and "Players can't cast spells from their hands unless there are no cards in exile."