The World Tree was also known as Kunmu and Jianmu.
When the World Tree still existed, it was the peak of the Nine Heavens and Ten Earths. This branch had fallen from the World Tree of old and was acquired by Kun Peng. Its leaves had also been made into prayer mats, possessing miraculous effects for comprehending the Dao. Shi Hao now used it as a weapon, though boys his age all liked playing with branches. Give him one, and he could be happy all day.
Shi Hao was like that now. He loved it dearly. It could be used as a weapon or turned into a barbecue rack, and it was impervious to water and fire.
In current legends, Kunmu and Jianmu were bridges connecting Heaven, Earth, humanity, and gods—the place of Tongtian.
However, according to legend, Kunmu had been felled during the Primeval Era, severing Heaven and Earth. Gods and humans had been separated ever since.
Of course, World Tree was the name that best represented it.
The truth was actually similar to the legends. The World Tree had indeed been destroyed in that great battle during the Late Ancient Immortal Era.
After that battle, the World Tree had at most only a few branches left, like the ones here now.
Numerous Immortal Kings of the Foreign Land had acted, destroying the World Tree and the foundations of the Nine Heavens and Ten Earths.
Every great realm had a World Tree or something that served a similar purpose.
It was a Realm-Fixing Object, a treasure that suppressed a realm—the manifestation of Heaven and Earth Laws. It carried a realm's Great Dao and formed that realm's foundation.
The Nine Heavens and Ten Earths were incomplete now, and the lack of a World Tree had much to do with it.