Black, Jack

When Black Jack attacks, exile the top 2 cards of
your library. Then target opponent exiles the top 2
cards of their library.

If the total converted mana cost of your cards by this
card is greater than the opponent's cards exiled by
this card and the total converted mana cost of your
exiled cards is less than 21, you may cast those spells
this turn and those spells cost {2} less.