Something seems off still about the Impregnable Formation. I went to the effort of getting the 5 banners and incubating them with Heaven-Mending, then equipping them to cultivators of the correct laws (had to check since most of them except Earth use the Feeding element.) Placed them in according to the required law positions, they're all Demi-God or Primordial State, over a million Qi each. Only the Pillar is activated.