A wall of strong wind rises from the ground.
You can shape the wall in any way you choose so long as it makes one continuous path along the ground.
The strong wind keeps fog, smoke, and other gases at bay.
Small or smaller flying creatures or objects can't pass through the wall. Loose, lightweight materials brought into the wall fly upward.
Arrows, bolts, and other ordinary projectiles launched at Targets behind the wall are deflected upward and automatically miss. (Boulders hurled by Giants or siege engines, and similar projectiles, are unaffected.)
Creatures in Gaseous Form can't pass through it.
Lifting your palms, a symphony of whistling winds surges as if conjured from the earth, forming an invisible barrier that sweeps away any unfortunate creatures caught in its breath.