Chu Xuan was confused. Since they were not enemies, why did the human race of the nine zones not have any legends about the giant race?
Fortunately, Daoist Flying Cloud knew the answer to this.
When the giant race entered the nine zones, they were extremely powerful. They occupied large swathes of territory and protected the weak human race at that time.
This was not unnatural, as giants and humans looked identical other than the size difference.
Furthermore, after the human race had cultivated the body-tempering technique of the giant race, their bodies had started to become stronger, as well as larger, which reduced the differences even further.
The human race was born weak, but they were indomitable. They somehow survived the various calamities.