Don't Let Me Stay Up All Night

As everyone knows, there is a power in the southern region that absolutely cannot be provoked—the Grass Hall. 
The eldest disciple is the Sword Saint of the southern region, with a godly understanding of swords. 
The second disciple is the Eternal Empress, who ruled an era. 
The third disciple is a great scholar of the current generation, the reincarnation of the immortal of literature. 
The fourth disciple is the reincarnation of a demon god, suppressing the Nine Hells. 
Lu Changsheng: Me? I'm nothing special, just their master.

I See the Aura of the Great Emperor in All My Disciples

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…

The Ninth Star Core!