Overview
In Shaman King, Hao initially appears as one of many unnamed observers to Yoh Asakura and Tao Ren's match for the final qualifying spot for the Shaman Fight and resides by the Matagawa River in Tokyo with the Spirit of Fire. In his first formal appearance in Reincarnation 78, he is introduced as Hao (ハオ?), a powerful shaman who Yoh notes has an uncanny resemblance to both himself and the Patch Officiant Silva. Accompanied by a number of followers, Hao declares his intention to create a shaman-only world and expresses an immediate interest in Yoh as someone who Hao will need in the future. Hao continues to observe Yoh and his development throughout the series for the intention of eventually claiming Yoh's soul as part of his own. Hao also develops an interest in Anna Kyoyama after realizing she had the power to defeat the shikigami familiars he created and because of her strong resemblance to Asanoha Douji, his mother in his original incarnation.
During the second round of the Shaman Fight, Yoh and his friends gradually learn that a number of shaman hold personal vendettas against Hao for how he has hurt them in the past. They also learn that he was somehow involved in the Shaman Fights from 1000 years ago and 500 years ago. It is eventually disclosed that Hao was once the founder of the Asakura family and had gained great prominence as a diviner for the Imperial Court; however, he eventually developed deep hatred for humanity as a whole and attempted to become Shaman King to destroy them. The Asakura family was able to defeat him, though Hao's mastery of esoteric onmyouji arts allowed him to be reborn 500 years later as a Patch Priest and then in the present when his efforts to become Shaman King failed a second time. When the present Hao's surname is announced to be "Asakura" during the Shaman Tournament, Yoh initially tells his friends that Hao is his distant ancestor, though he later reveals that during Hao's second reincarnation, Hao was reborn as Yoh's twin brother, thus explaining their resemblance.
In present Shaman Fight, Hao is soon established as the most powerful participant with 1,250,000 furyoku at his disposal and the powerful Spirit of Fire as his guardian ghost. In addition, he is able to read minds, allowing him to anticipate the actions of his opponents beforehand. In addition to his resemblance to Yoh, Hao exhibits a surprisingly easy-going affable attitude, similar to Yoh's personality.
However, he has deep contempt for ordinary humans and is extremely ruthless towards his opponents. Though he has gathered a number of loyal followers, he actually trusts very few people, expressing his inner thoughts only occasionally to his teammates Opacho and Luchist Lasso. Out of hatred for humanity, he espouses the belief that the destruction of humanity will allow the planet and other animals that humans abused to be saved. Because of his overwhelming power, he has allowed people to worship him as god and appears to have developed a superiority complex, regarding all other beings as his inferiors, a belief made more dangerous by his ability to back up this claim. His most distinctive motif is a star design he wears upon his clothing and he is usually seen wearing a long cloak over his trousers.
However, in spite of Hao's disdain for humanity and overwhelming power, Yoh expresses the belief the way to defeat Hao is not through a confrontation of power and the destruction of his soul, but through the heart.
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