black flame pillars

great pillars of black flame explode from the ground spewing off in different directions, frostbiting anything that they hit the pillars themselfs are 5 ft in diameter the range and how many there are are determined by 2 rolls of a d20. dealing continuous 2d12 damage to anything inside one of the pillars. As the creator and controller of these pillars the player can lift the pillars of black flames and throw them at any target they so choose (one pillar at a time) If they choose to do this it is determined by the roll of a d20 anything below 15 is a fail.