Yi Yu's body training technique has its foundation. The effect is getting weaker and weaker just relying on the energy between heaven and earth. It seems that it has reached a bottleneck. It's not against trying the method taught by Luo Jiu. As for the pain, I have not experienced it.

PA!

when Yi Yu clapped his hand, the high Danlu had been opened, and several kinds of medicinal materials flew out of the Xumi heaven and earth belt. When he was in Sancai Town, he purchased them from the underground tower. The medicinal materials were added to the Dinglu stove, which cost him more than 30 refined yuan coins....