Indeed, while he did not know how the willow tree knew, it was right.
When Shi Sheng obtained the core of the first star, the guardian spirit of the star core said.
At that time, the senior who created a peerless cultivation technique like the Chaotic Star Record did not use the power of the stars to reach the Peak Stage of cultivation!
Therefore, he used his star power to condense eight star cores.
In his estimation, only with the ninth star core could one perfectly reach the Peak Stage.
Therefore, even if Shi Sheng obtained the eight star cores, he would not be able to cultivate the Chaotic Star Record to the Peak Stage!
He was also unable to reach the Peak Stage of the Martial Dao with the Dao of Stars!
Therefore, after Shi Sheng obtained the eight star cores, he had to think of a way to condense the ninth star core to reach that realm!
And now, according to what Senior Willow Tree said…
