This substance gave people the feeling of a Seventh Stage Venerable's illusory reality.
However, it was of a higher level than the "illusory reality."
Specifically, it was very similar to what Song Shuhang had seen in the dream of the destruction of the Immortal World. When that immortal built his tomb, he used a technique that was between illusion and reality.
"Eh? Why are there so many of them this time?" Great Eastern Monarch was puzzled.
Last time, when the eleventh level had opened, the amount of "mysterious substance" that had come out had been extremely small. Great Eastern Monarch had used the word "permeate" to describe the amount of "mysterious substance."
If he hadn't been in a coma for ten months and collected all the mysterious substances that had seeped out, it might not have been enough for him to use even once.