The story of Haotian Mirror

Once Haotian had taken charge of the Heavenly Court he hung the Haotian Mirror before the Numinous Empyrean Hall. Its light swept the clouds and the mountains and rivers below, and the officers of heaven used it to check for demonic vapour and to pass reports of the three realms.

When something stirred below, the Jade Emperor ordered the officer on duty to turn the mirror, and the image settled on the cave or the country where the trouble was. Once the place was fixed, the heavenly soldiers took their orders and went out of the southern gate.

After each inspection the officers covered the mirror with cloud-vapour and returned it to the hall. The Haotian Mirror never went below with ordinary heavenly officers, and was always kept as an imperial instrument of the Numinous Empyrean Hall.