Douluo: There is a Yao Lao living in my body

What does it feel like to have a medicine master living in your body?
When Yu Xiaogang was instilling the "Ten Core Theories of Martial Soul" into Tang San, Yao Lao was already teaching Yang Fan to practice fighting spirit.
When Yu Xiaogang asked Tang San to run back with the stone on his back, Yao Lao had already refined the Fiery Pill for Yang Fan.
When Tang San was practicing Xuan Tian Gong, Yao Lao silently took out a book of Burning Decisions...
This book is also known as "Do you know about alchemy?" and "Sorry! This continent is not only about soul power."