Bituminous Blast [Planechase 2012]

Set: Planechase 2012 Type: Instant Uncommon Cost: {3}{B}{R} Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.) Bituminous Blast deals 4 damage to target creature.