Air Walk is a 16th level cleric Utility prayer that was introduced in Divine Power.
Air Walk
Cleric Utility 16
With deliberate steps, you stride upward on luminous clouds.
Personal
Effect: Until the end of the encounter, you gain the ability to move on air as if it were a solid surface. If you end your turn more than 2 squares above a solid surface, you descend gently until you are 2 squares above one.