Njöror the Romantic

Target opponent reveals their hand. You choose
a nonland card from that player's graveyard or
hand and exile it. You may cast that card for as
long as it remains exiled, and you may spend
mana as though it were mana of any color to cast
that spell.
Foretell {1}{b}{u} (During your turn, you may pay {2} and exile this card from your hand face down.
Cast it on a later turn for its foretell cost.)