Chaosborn Muse

At the beginning of each player's upkeep, that
player exiles all cards from their hand face up.
Any player may play cards exiled this way until
end of turn, and may spend mana as though it
were mana of any color to cast those spells.
At the beginning of each player's end step, if that
player has no cards in hand, they may scry 3,
then draw three cards.