In the end, the Giant King left. Lin Feng did not pursue him, because so what if he caught up? He had relied on the eruption of power of his internal universe, and acquired strength comparable to a Perfected Lord.
Yet it was still impossible to kill the Giant King.
This was because once one became a Perfected Lord, or a Chaotic spirit beast, their life-preservation abilities would be extremely strong. Unless the difference in strength was too great and one had overwhelming power, or one had methods to counter it, it was almost impossible to kill a Chaotic spirit beast.