Tai Chi.
This was the technique chosen by Lin Yun.
He had already studied over two hundred martial arts techniques, and many of them were mastered to a high level. He was exceptionally skilled in various power exertion techniques, some of which held a striking resemblance to Earth's Tai Chi.
Tai Chi was a martial arts philosophy, where two techniques were most famous, Tai Chi Fist and Tai Chi Sword.
Lin Yun opted to learn Tai Chi Fist.
Because, to Lin Yun, a weapon was an extension of the body. The Tai Chi Sword was actually a better method for applying the principles of Tai Chi, but Tai Chi Fist was the fundamental.
According to the information provided by the Cosmic Trading System, Tai Chi was divided into Elementary, Intermediate, and Advanced Level, corresponding to Level 1, Level 2 and Level 3 martial arts techniques respectively.