The solution Ling Xiaolong left behind was the nine blood chains binding the man tightly, keeping him imprisoned inside the blood space. These chains were actually nine parts of his soul. As long as even a single one existed, that man could never be killed or vanish.
This was the doing of Ling Xiaolong. He was so powerful that he easily divided the man's soul into nine parts without the man's knowledge. The man always felt that the blood chains were simply ropes imprisoning him inside the blood space, but now he understood that nothing in this space was simple.
Although the nine blood chains were parts of the man's soul, they were under Ling Xiaolong's control due to the profound runes inscribed on them. The man could do nothing about these runes.
Now that one of the chains had disappeared, it meant the man had lost one-ninth of his strength in terms of soul power.