Tornado. The air spirit can spend both its actions to spin, generating a tornado with a 10' radius. Anybody who enters or stars their turn in the tornado is subject to a 6d6 vital attack, or take 3d6 blunt damage and be knocked prone.
Amorphous. The air spirit can fit through any gap, changing its shape at-will.
Hard-to-see. Air spirits are made of air, and thus largely transparent. They are not bound by their maximum dice pool when using stealth. When stationary, an air spirit is invisible.