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When he had persisted for two hours, the pain and fatigue finally lessened somewhat, and his body seemed to be adapting to the training. He felt that he could probably endure another two hours. He had previously thought his limit was one hour, which clearly underestimated himself.
Moreover, the greater his determination, the stronger his pain tolerance. He actually understood this principle.
The first day was indeed somewhat unbearable. There had been moments when he almost felt like he was going to die, but nothing happened. His body was incredibly strong, overcame these hardships, and adjusted well.
The power contained within the black smoke constantly varied. Sometimes, digesting it required tremendous effort, which posed a test for him, demanding the strength of nine bulls and two tigers to pass. Other times, it was effortless, even for several hours in a row.
Since he'd come this far, he could not back down.
