Five kilometers of annihilation
Bai Zemin confirmed the evolution requirements of the new Superhuman Health skill but seeing that he needed First Order Soul Stones in addition to Unclassified Soul Stones he decided to stop temporarily.
Although he still had approximately seven First Order Soul Stones left, Bai Zemin knew that such Soul Stones were currently precious. Unless the First Order creatures suddenly became normal like the other monsters or their numbers increased exponentially he was not willing to spend all his Soul Stones.
After all, he still needed equipment for himself, for his subordinates, even to evolve other skills.
In fact, were it not for the current situation they were in it was improbable that he would expend one of the few First Order Soul Stones he had in his inventory.