Song He wasn't exactly struck by a sudden inspiration.
After all, in a certain sense, Shenyao Heavenly Cave at Shen Ye Feng could be considered the "netherworld"—filled with souls that had lost their bodies.
But the consciousness within mere Divine Sense was different from a soul and spirit; souls were tangible entities that could still practice cultivation and were consistent with the laws of heaven and earth.
It is said that an entire sect is comprised of those who cultivate souls.
Cough cough, I'm thinking too far ahead.
The current small world definitely wouldn't be able to sustain the entry of so many cultivators' souls—nor would cultivators willingly allow their souls to enter a world controlled by the Spiritual Leaf Sect.
So, could part of the soul that contains memories be severed and then enter this world? It should be easier to repair a soul depleted of power.