Metaphysical / Paranormal event
The Vestiges of Bahamut newly reborn into the mortal world quickly learned of their vulnerability in such a state. Following the lead of Amaterasu, they joined themselves to the regional phenomenon of Chuth known as a highstorm.
A highstorm the likes of which chuth or the world has ever known was born. The vestiges of Bahamut ride the storm each time it's born, bringing their power to the material plane once more. In this state these once distant gods found they are far less vulnerable to shattering.
The Highstorm as it soon grew to be called always originates from somewhere around Chuth, and travels west around the world.