Itazura, Lingering Wick [Mystery Booster: Commander Edition]

At the beginning of your upkeep, exile the top three cards of your library. Each opponent secretly chooses a number 0 or greater. Then those numbers are revealed. Choose an opponent with the highest number. Itazura deals that much damage to them, then they may cast a spell from among those cards without paying its mana cost. You put a card from among them that wasn't cast this way into your hand.