Windguard (Stronghold Augmentation)

Windguard: When creating this augmentation, choose one face of the wall. A wind wall protects that side of the wall.
When creating the augmentation, you can choose to include the first 10 feet above a wall of stronghold space in the augmentation (for instance, to protect your wall-mounted guards from arrows). Remember that the windguard works against objects going in either direction.
Caster Level: 3rd; Prerequisites: Craft Wondrous Item, wind wall; Market Price: 3,000 gp.