Vacuum

You choose a point in sight, you create an area 10 ft diameter, the air inside it vanishes leaving a vacuum, suffocating anything inside, that needs air. Non air breathers immune. Flames in area will be extinguished. Any creature in or entering area must on a Dex Save, vacate area, on a Dex fail creature's fall unconscious.

On higher level's 5,11,16,20, the diameter increase's 5ft per level.