"True strength is to know the extent of one's weaknesses."
Master Lei Kang is a wise and powerful Pandaren monk, highly trained in the martial arts of the pandaren, and well learned in the art of zen. Though he is still young, (approaching mid-life), he is described as being one of the most powerful pandaren who ever lived. He is powerful enough to either outstrength or outwit anyone who challenges him, as he has done countless times before. His great knowledge of philosophy, martial arts, and politics made him a central figure and role model for all his race.
However, he lost much of this praise after he defected from the Alliance to instead join the Uuruk uprising. Impressed by their fierce determination and honorable motives (combined with his noticing of the injustices condoned by the society he was a part of), Kang abandoned the Alliance he once swore fealty to. This shocked the entire Alliance, especially Pandaria. Many pleaded with Kang to return, but he simply replied, "I cannot forgive a society that is too proud to admit its own faults". Thus, he joined the Uuruk, swearing loyalty to Lady Sylvanas. Since then, he has used his pandaren ways of thinking to predict enemy movements and tactics. He has also caused the selling out of more than a few Alliance territories. His great wisdom and battle prowess has made him an indispensible asset to the Uuruk empire.
HistoryLei Jing Wu Kang was born to a peasant family in the small town of Te Ching in the pandarian countryside. This is where he grew up, and where he developed his inquisitive and thinking mind. As a cub, he thought about everything; life, its purpose, destiny, strength, and honor. He developed a keen philosophical mind, and he was fascinated with the exotic fighting styles he witnessed in his childhood. This is when he made the decision to become a monk in the Wushu Order (monks in service of the Emperor).
Kang was trained extensively in the art of Zhugguo Wushu, a martial art style developed by the pandarens, and more specifically, the wushu monks. The young pandaren learned quickly, advancing past beginner training in a matter of days. As he got older and more experienced, he began developing his own techniques, such as Chuan Yin, a fighting style that only used fingers for defense and offense techiques. He became famed across Pandaria for his incredible skill and vast wisdom. Eventually, he was given the rank of Master of the Wushu Order. He began training his own students, and even offered his former masters advice on honing techniques. In total, Kang mastered 79 techniques of pandarian martial arts, taught 70, and developed 6. He became a living legend, and he wasn't even 50 years of age (around 45).
With the rise of the Uuruk rebellion, the lands of the Alliance (including Pandaria) were thrown into unrest. They began hunting down "rebels", which were basically any suspicious citizens they could get their hands on. With towns and even cities falling to the uprising, many refugees emigrated to other lands. Many refugees and citizens came to Lei Kang to seek wisdom and encouragement. He urged them, "The universe has a way of sorting itself out. Stay strong, brothers and sisters". Still, the uuruk closed in on Alliance territory. As tension rose, governments began arresting and torturing innocents if they had even slight suspicion. Kang was apalled by this, by governments who punish its citizens for intangible "crimes". Eventually, he had enough. He abandoned the Alliance, turning against his own people. He encouraged as many of his followers as possible to follow him. These followers became known as the Sheng Zhao, rebel pandarens who swear loyalt to the uuruk, and more specifically, Master Lei Kang. Kang met with the uuruk leaders, among them, the dark elf queen Sylvanas. He swore an oath to her, promising to fight and die for the cause if necessary. He pledged his Sheng Zhao warrior monks to the cause as well, and thus began Kang's official betrayal.
His brilliant and wise mind was easily capable of predicting Alliance military movements. With his wisdom, the uuruk was able to gain the upper hand against the enemy. He became a valuable asset to the rebellion and to Lady Sylvanas, although the two had differing mindsets and ideas of how to accomplish objectives (which led to unstable relations between the two). Still, their motives remained in line, and thus they were able to continue on as allies.