Avatar: The Last Airbender did not save all its special abilities for the elemental Benders of its world. Figures like Ty Lee could learn to Chi-Block even without special powers, and by The Legend of Korra the paralyzing martial art spread to dozens of others throughout the world. Yet in looking back over the history of Avatar, it seemed questionable that Ty Lee would be the first one to develop such a world-changing art form.
With the release of Avatar Legends: The Roleplaying Game core book, fans indeed learn that she didn't invent it. It turns out Chi-Blocking dates back to a time long before Ty Lee, and its real origins make far more sense.
From its introduction in Avatar: The Last Airbender, Chi-Blocking proved to be one of the most effective martial arts a Nonbender could learn. By targeting specific points on a target's body, a Chi-Blocker could paralyze their limbs and render their ability to bend inert. Ty Lee was the only practitioner of the art in the original series, though it never really explored how she developed it. She did seem to have an affinity for seeing the "aura" of those around her that hinted at some ability to perceive the flows of chi that could assist the art, yet as the series progressed, this proved not to be a necessary component.
After all, Ty Lee taught the art to Suki, who then passed it on to several other Nonbenders learning to defend themselves. By The Legend of Korra the technique progressed to Amon and his Equalists, who wielded Chi-Blocking as a devastating weapon in their violent uprising. But the more the story progressed, the less its origins made sense. What was so special about Ty Lee, a young girl trained primarily as a circus acrobat, that allowed her to discover the art? The truth is that she may not have discovered it at all, especially since there were Air Nomads practicing it long before her.
Avatar Legends introduced a new character to the lore named Rioshon, who existed in the Era of Roku during the time of the Avatar before Aang. Rioshon was considered a skilled Airbender of the Western Air Temple, renowned for her ability to train students in the art of Chi-Blocking. She even passed the technique on to Princess Zeisan, Fire Lord Sozin's sister who abdicated her own royal titles in order to commit herself to Air Nomad philosophy. Embracing the teachings of pacifism were a key component for any student Rioshon accepted, serving as a far more sensible explanation for the martial art's origin point.
Though Chi-Blocking is so often used in the series with deadly efficacy, it's actually a rather pacifistic fighting style. Paralyzing an opponent can end a fight quickly without doing lasting harm, and given the Air Nomads' long spiritual history, it only makes sense that they would be even more attuned to the same auras and flows of chi than Ty Lee. Rioshon's introduction also addresses a question Avatar fans long had about whether or not Benders could even learn Chi-Blocking.
Though it is not stated that Rioshon invented the art -- Chi-Blocking is potentially an ancient art that dates back even before Roku's Era -- at the very least, it was not seen throughout the Kyoshi novels set in the time prior to Roku's. Fans still lack specific answers where those origins are concerned, but can be satisfied that the explanation from Avatar Legends feels more fitting than what could be posited previously.
The confirmation that Benders could learn Chi-Blocking also opens the door for stunning possibilities and combinations for future characters. Be it an Avatar who masters the art to expand their fighting prowess beyond Bending or even a Waterbender or Earthbender who combines Chi-Blocking with their own skills to paralyze foes from range, revealing more about Avatar's history only opens up more exciting avenues for its future.
