Kokuō (Spectre)

Kokuō (穆王, Kokuō), also known by the moniker Five-Tailed Dolphin Horse (五尾のイルカ馬, Gobi no Irukauma), is one of the Tailed Beasts created by the Creation of All Things technique. Prior to, and during, the events of the Fourth Shinobi World War, it was sealed within Han: a shinobi hailing from Iwagakure. However, after the conflict, its power would come to be divided into and  halves; only to be subsequently sealed within a notable Father and his only Daughter.

Background

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Prior to the formation of shinobi villages, Hagoromo Ōtsutsuki utilized his Creation of All Things technique order to extract and partition the chakra of residing within him. Through this act, nine Tailed Beasts were created; and to the one bearing five tails he bestowed the name Kokuō. As time moved ever forward, Kokuō would ultimately fall into the possession of Iwagakure. There, it was sealed within Han; where it resided until his capture by the criminal organization Akatsuki. They extracted Kokuō from Han, resulting in his death, and promptly sealed him within the physical remains of the Ten-Tailed Beast. There, Kokuō resided until the events of the Fourth Shinobi World War, where he was then re-sealed within a reanimated Han.

As the battle raged on, Kokuō would briefly take up residence within Naruto Uzumaki; where it lent its strength to the brave shinobi who faced down the. Eventually, the battle concluded and Kokuō was then released to peacefully wander the world as it saw fit. It then took up residence within the Land of Valleys, where it would eventually become a guardian of sorts to the local populous. In time, a Hidden Village would rise within the country and Kokuō would agree to a heartfelt request made by the people it willingly defended. Its power would be divided in two, Yin and Yang, in order to be sealed within the Kage of the new village...and his young daughter.

Personality
As a whole, Kokuō is a reserved individual. Whilst sealed within its host, silence is relatively commonplace. However, it has demonstrated a profound sum of manners; as evidenced by the old-fashioned terms it utilizes to refer to itself. In addition, Kokuō possesses a wisdom born of many years of life. Oftentimes, it will break its silence in order to share words of advice with its host; acting as a council on all matters that its wisdom would be welcome. Yet, despite its respectful tendencies and boundless wisdom, trust does not come easy for it. Kokuō has been sealed within host after host prior to being sealed within Han and was treated as little more than a weapon by Iwagakure. Regardless of his new home's kindness and the actions of Naruto Uzumaki during the Fourth Shinobi World War, it will take time for Kokuō to trust its hosts completely.

Appearance
True to its name, Kokuō appears pimarily as a horse of white hue; with its head closely resembling that of a dolphin. Upon its head are a total of five horns; two of which are long and pointed whilst three are shorter and located closer to the front. Kokuō's hooves, in addition to the tips of its tails and horns, are light brown. It also has red semi-rings underneath its eyes; which are a dark, blue-green hue. In terms of stature, Kokuō stands at a height that is considered "normal" for a Tailed Beast: amounting to several stories in total. Similarly, the "Yin" half of Kokuō appears as an aesthetic inverse to the norm. In terms of physique, there are no differences, but the most striking differences are in terms of hue. "Yin Kokuō" is coal-like in terms of hue with its hooves, and the tips of its tails and horns being black. The rings underneath its eyes are also black; with the irises themselves being blood-red.

Abilities
Being that Kokuō is a Tailed Beast, it has a significant amount of chakra. However, prior to its division into Yin and Yang halves, its power was effectively split in two. Based upon the assumption that power of Tailed Beasts are equivalent to its total number of tails, both halves of Kokuō are almost equivalent in strength to Isobu. However, despite its overall power level, Kokuō is defined by an extraordinary physical strength; a power that is epitomized through the utilization of its horns. In fact, when ramming enemies of comparable size, Kokuō is capable of sending another tailed beast flying back a considerable distance.

Kokuō also possesses the innate ability to utilize, an advanced chakra nature typically composed through the combination of the and  Releases. It can increase the temperature of chakra to its boiling point, which can then be employed in the form of steam. This steam is typically utilized in order to augment both its, and its host's physical strength to overwhelming levels. When in usage, this form of Boil Release causes the host to emit copious sums of steam from their body. On another note, due to the division of and, each halve of Kokuō affords its host the ability to access the appropriate element at a pronounced level.

Trivia

 * 'Kokuō' (穆王) literally means 'respectful king'. This name probably comes from the name of the tenth-century-ʙᴄ Chinese King Mu of Zhou (周穆王, Zhōu Mù Wáng). He's famous for the legend surrounding his visit to the sacred Kunlun Mountains (崑崙, 昆仑山, Kūnlún Shān), where he visits the goddess Xi Wangmu (西王母, Xī Wángmŭ; Literally meaning "Queen Mother of the West") so he can eat from her peaches of immortality. There is also an account of the King being shown a human-shaped automaton — a completely artificial, fully functional robot with internal organs and all. This might tie into Han's appearance and abilities. In Japanese, the name '穆王' is pronounced as 'bokuō', so the unusual 'kokuō' pronunciation used for the beast's name was probably meant to bring the word 国王 (king) to mind.
 * The kanji '穆' in Kokuō's name comes from the archaic adjective 'bokuboku' (穆穆), which means 'peaceful and lovely' or 'humble and dignified' and are also traits often associated with horses and dolphins.
 * According to Kishimoto in the second Naruto artbook, he tried to do a mix of a dolphin and a horse when he created Kokuō.