Typhoon Blast

Using the pure energy of the plane of air, you slowly suck the air around you into a ball of pure wind for 20 sec/3 turns, releasing on the 3rd turn to create a massive blast of air in a cone, creatures caught in the cone must make a con save, or take 2d6 force damage, and be pushed back 30 ft, or half of both if succeed on con save. in order to cast the spell, you must be in a area of 70ft, 70ft, 70ft