The Illusion Formation would not cause any direct physical damage.
It was to penetrate and disintegrate the martial cultivators who were trapped in the illusion array bit by bit.
With Fang Qiong's physique and the Holy Formation Prison Body Technique, he could directly absorb the spirit of the array formation.
Of course, if someone had set up a backlash or other protective formation in the formation,
with Fang Qiong's current strength, he probably would not be able to absorb it easily.
However…
This Immortal Encounter Sky Penetrating Mountain's illusion array seemed to have been intentionally set up by the person who set it up.
Such a high-level array formation did not have a backlash or protective array formation to protect it.
Perhaps the person who set up the spirit formation had also thought that someone would be able to break through the spirit formation and pass through it in another way.