As Zhang Yu crossed layer after layer of the Kunxu boundary, he could feel the concentration of Immortal Qi in the air continually increasing.
When he reached the Kunxu 13th floor, the Immortal Qi concentration had reached a 2% to 3% level, and in such an environment, even if he did nothing, his physical strength would naturally improve.
And when Zhang Yu arrived at the Kunxu 14th floor, the Immortal Qi reached a concentration of 3% to 4%.
Zhang Yu could feel that the various energies within his body became increasingly active in this environment, as if any martial arts or Taoist skills he performed would be enhanced layer by layer.
"In this environment on the 14th floor, just the daily operation of cultivation technique makes the cultivation effect much stronger than on the lower floors."
Zhang Yu sighed: "Compared to the Kunxu 1st floor, perhaps just lying here every day progresses faster than the students struggling with cultivation on the 1st floor."
