Following his duty as a member of the Asakura family, Yohken entered the Shaman Fight of 500 years ago to defeat Hao Asakura, which he did, with the help of Matamune, Hao's former companion.
Yohken entered the Shaman Fight of 500 years ago to defeat Hao Asakura with the help of Matamune. This was following his duty as a member of the Asakura family. Matamune was Hao's former companion. He did Hao Asakura.