"How did the level of cultivation of this human boy become so powerful?"
To resist Zhang Ruochen's Sword Qi, Black Skeleton Flood-dragon King wielded the Roaring Flame Hammer twelve times. However, not only did it fail to block Zhang Ruochen's Sword Qi, but it was also pushed back by twelve steps.
At this moment, its arm was tingling with pain, and the Roaring Flame Hammer in its hands kept shaking.
Even if Black Skeleton Flood-dragon King were unscathed by such great power, it would not be able to match Zhang Ruochen's skills, even at his prime.
It was not difficult for Zhang Ruochen to defeat Black Skeleton Flood-dragon King because they were fighting at the bottom of the sea, where Black Skeleton Flood-dragon King's strength was suppressed to its lowest level.
Zhang Ruochen made a tremendous jump to the next realm by breaking through to the Fish-dragon Realm, so his level of cultivation had increased by leaps and bounds.