Refining a Chaotic spirit treasure might be slightly more complicated, but as long as he obtained the approval of the artifact spirit, the rest would be very simple. Lin Feng easily inscribed a mental imprint in the Quadruple Spirit Lamp.
The reason why he did not inscribe a perfected spirit imprint was that perfected spirits were the foundation of cultivators, and could not be lost. Even a Perfected Lord could not split out any of their perfected spirit.
Even if they could split out a little of their perfected spirit, if it entered the Chaotic spirit treasure and the Chaotic spirit treasure was destroyed, wouldn't their perfected spirit also disappear? The gains would not make up for the losses.
Hence, no Perfected Lord would use a perfected spirit imprint to refine a Chaotic spirit treasure.