The reason was simple, he didn't need it at all.
"My Life Wheel Scripture has the ability to prevent the prying of fate, and its effect is definitely better than this technique. This technique can't even be considered as a trivial appendage for me."
Su Nan shook his head and looked at the second technique, Change one's face.
It was clearly an upgraded version of Boneshifting.
Although Boneshifting could help him transform into various appearances, he couldn't change into beings without flesh and blood.
For example, the Paper Puppet Demons in the City God Temple or the Bone Demons in the White Bone Cave.
"This technique is good. If I get this technique, maybe I could transform into a Bone Demon and possibly enter the Bone City."
"But if I choose this technique, wouldn't it mean that Boneshifting would be replaced? I could still only use one technique?"