From Compendium of Worldly Lore
Needs review
Source: Monster Manual
Description: The creature can come to a halt in midair.
Prerequisites: Fly speed
Required for: Wingstorm
When flying, the creature can halt its forward motion and hover in place as a move action. It can then fly in any direction, including straight down or straight up, at half speed, regardless of its maneuverability. If a creature begins its turn hovering, it can hover in place for the turn and take a full-round action. A hovering creature cannot make wing attacks, but it can attack with all other limbs and appendages it could use in a full attack. The creature can instead use a breath weapon or cast a spell instead of making physical attacks, if it could normally do so. If a creature of Large size or larger hovers within 20 feet of the ground in an area with lots of loose debris, the draft from its wings creates a hemispherical cloud with a radius of 60 feet. The winds so generated can snuff torches, small campfires, exposed lanterns,and other small, open flames of non-magical origin. Clear vision within the cloud is limited to 10 feet. Creatures have concealment at 15 to 20 feet (20% miss chance). At 25 feet or more, creatures have total concealment (50% miss chance, and opponents cannot use sight to locate the creature).Those caught in the cloud must succeed on a Concentration check (DC 10 + 1/2 creature's HD) to cast a spell.