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The three formations of Zhongnan Mountain: the Celestial Nine Platforms Array for Gathering Spirit, the Iron Bamboo Array as a Blind, and the Chiseling Dragon Hundred-Span Cliff should be considered the tomb-guarding formation.
The Formation of Hundred-Foot Cliff is quite good, within a hundred-foot space neither human nor ghost can invade, it should be a level higher than the Blind, but such things are clearly consuming Spiritual Energy, which will basically not be realized in this world.
After a cursory glance at the remaining astronomical and numerical techniques, it is apparent that this is astronomy and mathematics, not a Spell, but a prerequisite for advancing in the study of formations.
The star-gazing techniques recorded above might even be more advanced than those of the Imperial Astronomical Observatories of the East and West.
Xu Xuan closed the book and asked, "Do you know of any news from the Tai Yi Sect?"
