Rakdos Vanguard

The first spell you cast each turn gains Cascade
the Bank if you control one red and one black permanent. (A multicolored red and black card
counts for either red or black.) (To Cascade the
bank, exile cards from the top of the bank until you
exile a card that costs less. You may play it without
paying its mana cost. Put the exiled cards on the
bottom of the bank.)