Supervillains in Kung Fu movies are invaribly the coolest parts of the genre, because they are nearly always impervious and superior, both in intelligence and fighting ability, to anyone else. Their power is generated through sheer force and will, and only the hero(es) preternatural lust for revenge usually defeats these awesome Kung Fu menaces.
In BORN INVINCIBLE, you get probably the most bizarre, yet realistic, supervillain in the whole of the genre. Carter Wong's Tai Chi training (a style developed by a woman), starting from a small child, results in iron skin, snow-white hair, and a high, feminine voice. This Tai Chi master becomes an unstoppable thug-chieftain who can fight a deadly duel and, simultaneously, carve a Chinese yin-yang symbol in the earth with his feet. This powerful supervillain operates from a source of disipline that is downright scary; Wong is entirely invincible but for his one weak point. When you see how relentless Wong's killer-master is, you can't help but relate to the terror in the heroes' faces when they have to take him on. Fact is, if not for the honor of their school, which is paramount to the students trying to take revenge for Wong's murder of their teacher, nobody would mess with the Tai Chi master, since it is considered by the most learned monks to be certain death.
What separates Joe Kuo film villains, characters like Wong's and the great Ghost-Faced Killer from MYSTERY OF CHESS BOXING, is that Kuo puts one scene in there to show us the supervillain is also human. Wong's character is stopped from a killing rampage at one point by a white-haired nun, and there's a moment when Wong seems to reflect on what he IS, a killer, as opposed to what he trained to become, an otherworldly kind of priest attuned to nature and the inner forces like the nun. The fact that Wong won't, or can't, stem his bloodlust and sadism is his undoing. There's a lot going on in BORN INVINCIBLE aside from the superior fighting skill of the actors. One of the best Kung Fu films based merely on this unusual depth of character, and a knock-out all the way.