A martial grandmaster breakthrough required both an accumulation of experience and an element of luck.
This was something that Luo Yunyang had heard from Teacher Xie. According to Teacher Xie, 10 years ago, when he had been just a top-notch martial master, a coincidental chance had allowed his source core to break through his body's binds and turn him into a martial grandmaster.
Becoming a martial grandmaster didn't just depend on physical capabilities and accumulated experience. A slight comprehension and understanding were also necessary. If someone lacked this aptitude, they would find it difficult to break through the boundaries of a martial grandmaster even if their body had accumulated enough energy.
This was also why there were so few martial grandmasters in the world after so many years.