At that time, the Old Dragon Emperor used only the highest standards to look at the current cultivators.
He believed the human race was quite impressive and creative.
The cultivation industry had developed for so many years, and such level of array formations should have been the norm long ago for array masters.
Thus, he forced Lu Wenwu to learn a lot.
Whether actively or passively, he memorized it with his mind and body.
You might not know how to build it, but at least you should know how to solve it.
So, as soon as Lu Wenwu entered Celestial Secret City, he discovered the incomplete grand array, which the cultivators of the Immortal Dao Alliance had patched up with some messy "codes" and barely made it run in a strange way.
However, the Old Dragon Emperor never expected that such an important and powerful array inheritance like the Nine Heavens Ten Earths Demon Slaying Array would face severance in its home of the human race.
