Balance on the Sky(Tome of Battle: The Book of Nine Swords, p. 75)
Shadow Hand (Stance)
Level: Swordsage 8 (Three Shadow Hand maneuvers),
Casting Time: 1 swift action
With arms spread wide, you step onto the air.
You gain the ability to use air walk (PH 196) on yourself only. You must keep at least one hand empty while using this stance. Moving upward requires you to spend 10 feet of movement for each 5 feet of elevation you gain.
You gain the benefit of air walk only while you maintain this stance. If for some reason your stance ends while you are in midair, you fall to the ground.
This stance is a supernatural ability.