The Leap Through Space
After reaching the Stage of Rejuvenation, Leon's strength and regenerative abilities improved considerably.
Apart from that, he also gained much insight into demons and the nature of their cultivation. There was hidden knowledge that could only be obtained from their blood.
When humans hear about demons, they think of them as an evil and bloodthirsty race with powerful bodies and strong regenerative abilities, making them difficult to kill as they spread malice and destruction to all who cross their path.
However, was such a powerful race always born that powerful?
The answer was no—or at least, that was the answer Leon arrived at after refining and absorbing the blood essence of 30-odd demon corpses.
Demons were not born powerful, but they had an inherent ability to grow powerful quickly. It was the ability to assimilate the bloodline of other races and make it their own.
From Leon's point of view, it was a type of blood cultivation.