What Is The Strongest Breathing Style In Demon Slayer?

"Demon Slayer: Kimetsu no Yaiba" is finally giving fans new material following the beginning of Season 2, which retold the events from the massively successful "Demon Slayer: Mugen Train."

"Mugen Train" saw Tanjiro Kamado, Zenitsu Agatsuma, and Inosuke Hashibira team up with the Flame Hashira Kyojuro Rengoku to battle against an upper rank demon. On the train, Tanjiro asks the Hashira if he's heard of the Hinokami Kagura, to which Rengoku says he's never heard of the term, but the former Flame Hashira may have some insight. Tragically, Rengoku meets his end on the train, and the other demon slayers are then tasked with a new mission in Japan's Entertainment District.

But before Tanjiro and friends head off on their new mission, Tanjiro goes to Rengoku's familial home to recount his last words and learns some vital information on his trip. According to Rengoku's father, it turns out that there's actually one Breathing Style that's stronger than the rest.

For those that don't know, Breathing Styles are a type of swordsmanship skill used by the Demon Slayer Corps that also incorporate the breathing technique called Total Concentration Breathing. By using Total Concentration Breathing, demon slayers are able to enhance their physical and mental capabilities and can increase their strength, speed, focus, and more, allowing them to perform their advanced Breathing Styles.

At the Rengoku home, Tanjiro learns from the Flame Hashira's father, Shinjuro, that Tanjiro's hanafuda earrings passed down from his own father are actually a marker of Sun Breathing users. Shinjuro also divulges that Hinokami Kagura is also called the Sun Breathing Style, and it's actually the first to be created. According to Shinjuro, all of the other Breathing Styles (Fire, Water, Wind, etc.) are derived from Sun Breathing, which is noted as the most powerful style of them all. 

While Tanjiro believes he comes from a long line of coal workers, the manga later reveals that only his family uses the Sun Breathing Style and it's passed down each generation, along with the hanafuda earrings (via Demon Slayer wiki). Tanjiro has a long way to go to mastering this Breathing Style in the anime series, but we may get to see his skills develop in the ongoing season.