The hidden books in the attic all come from annual Earth Sacrifice Ceremonies.
The reason the knowledge involved in the tests of the Megrez Immortal Mansion can continuously update is because it is written on the Earth Book created by Megrez that each Earth Sacrifice Ceremony requires the burning of books as offerings to the earth.
These burnt books are actually directly transmitted to the Megrez Immortal Mansion through the ceremony, where they are read and absorbed by the clone left by the Immortal Mansion Master to make test questions.
Wu Chang took a quick look around the attic. Although there were many books, they all contained common knowledge, with no cultivation techniques.
However, to the Megrez Immortal Mansion Master, cultivators who can complete the five trials naturally wouldn't be lacking in cultivation techniques.
Unlike Kaiyang, Megrez is focused on researching arrays and planning, with no time for alchemy and artifact refining.
