Kinkaku

was one of Kumogakure's Gold and Silver Brothers.

Background
The Gold and Silver Brothers were the most reviled criminals in the history of Kumogakure. Once, they were assigned to capture the Nine-Tailed Demon Fox, but were swallowed whole. However, they survived, and thrashed inside the tailed beast's stomach for two weeks, eventually forcing the Nine-Tails to regurgitate them. When in its stomach, they survived by eating the flesh of the beast. A portion of the Nine-Tails' chakra remained within them, giving them a large chakra reservoir, allowing them to use the five Treasured Tools of the Sage of the Six Paths without dying from the large chakra consumption. During the peace ceremony between the Second Hokage and the Second Raikage, the two brothers staged a coup d’état that left the Hokage on the brink of death. Sometime in his life, he met Kakuzu.

Appearance
Kinkaku was a burly shinobi, with a muscular build and towering stature. He seemingly possessed long, gold coloured hair with prominent dark tips, arranged in a style reminiscent of a Native American headdress. These features are accentuated by the presence of two distinctive horns that emerge from the abundant hair on his head as well as a light-coloured rectangular marking on his nose. Unusually, he had the same characteristic whisker-like marks on his face as Naruto Uzumaki.

His typical attire was comprised from the standard Kumogakure Flak Jacket, worn over a high collared sleeveless uniform, and a pair of simple wrist-guards. The kanji for is tattooed upon the shoulder of his exposed left arm.

Personality
Kinkaku was, like his brother, considered to be a disgrace to Kumogakure due to their belief of deceit and betrayal being battle strategies. Despite this, he is considered to be a loving brother, showing great fury when Ginkaku was sucked into the Benihisago by Darui.

Abilities
Kinkaku and his brother were well known for their prowess during their lifetime, so much so that one Kumogakure shinobi trembled in fear when he saw them and provoked the Fourth Raikage enough into almost disregarding his duties as leader of the Allied Shinobi Forces to personally confront the pair. According to Ao, the brothers both possess enormous chakra reserves with traces of the Nine-Tails' chakra mixed in due to being swallowed and regurgitated by the Nine-Tails after surviving two weeks inside its stomach.

Treasured Tools
The brothers wielded the five Treasured Tools of the Sage of the Six Paths, all of which cost a large amount of chakra, enough to kill normal humans before they can utilize the tools properly. The brothers can use them due to the combination of their high chakra level and the Nine-Tails' chakra. By combining the Benihisago, Kōkinjō and Shichiseiken, they can capture their opponent's and body, sealing them away for good. The Bashōsen allows them to create any of the five basic elements.

Jinchūriki Transformations
Despite not being an actual jinchūriki, he had absorbed a large amount of the Nine-Tails' chakra and ate some of its chakra flesh while trapped in its stomach. So much so, that he was able to enter a more muscular version of Naruto Uzumaki's six-tailed form with one tail vastly longer and thicker than the others. However, it lacks the Nine-Tails' skeleton. Kinkaku also retains his consciousness, unlike Naruto, who lost to his bestial instincts in this form, likely due to the absence of the beast itself, though rage still seems to be the trigger that makes him enter this form.

In this form, he is seen using his chakra tails to strike with great force and range, block a torrent of kunai with said tails, throw a giant rolling tank aside and easily break out of the Shadow Imitation Technique in seconds. However, despite its similarity to Naruto's higher forms, it seems to lack the corrosive chakra cloak that Naruto gains in Four-Tails and beyond.

Shinobi World War Arc
In preparation for the Fourth Shinobi World War, Kinkaku is resurrected by Kabuto Yakushi to fight against the Allied Shinobi Forces. Emerging from the sea near the Land of Lightning's coast, alongside his brother and among the White Zetsu Army, the two engage the opposing First Division. Confronted by Darui, he recognises that he had inherited the Third Raikage's techniques, indicating that he must be rather strong.

With Darui's remark, he says that even those from Kumogakure had lost respect for them. After Atsui and Samui arrive, Kinkaku retrieves the Bashōsen and Shichiseiken from his mouth, giving the latter to his brother, whilst the Kōkinjō wraps around his arm. Hitting both siblings with the rope, he draws out their word souls, so that Ginkaku can curse them. Reading the special word from the thrown sword, Kinkaku burns Atsui's arm, which forces him to say his forbidden word, causing him to be sealed. While his brother takes Samui hostage, Kinkaku attempts to attack Darui, only to have his arm cut off. Darui then attacks both brothers, freeing Samui but coming into contact with the rope around Kinkaku's severed arm, which the latter had kicked. He then cuts Darui's word soul and Ginkaku records it.

When Darui mistakenly utters his taboo word, he was inadvertently able to change his most said word whilst being sucked into the Benihisago, cancelling the sealing unbeknown to the brothers. Disarming Ginkaku and knocking him into Kinkaku, Darui then commandeers the other tools. Launching his blade at the latter, he deflects the sword, only to be struck by another bombardment. Darui uses this opportunity to curse and seal Ginkaku, causing Kinkaku to go berserk and enter into his six-tailed form.

Although Darui apologises for Ginkaku, Kinkaku wreaks havoc on the battlefield, killing many despite Chōza Akimichi's efforts. Observing the Kohaku no Jōhei in Darui's possession, he concludes that they were planning to seal him within it, before ambushing and almost killing Darui if not for Kitsuchi's strike. Deflecting a barrage of kunai, Kinkaku fails to see Chōji Akimichi's approach, but he repels his attack using strength alone. However, this was merely a distraction, so Shikamaru Nara could bind his shadow.

Breaking free with ease, Kinkaku is instead taken control of by Ino Yamanaka, when he tried to kill Shikamaru. Forcing him to respond to Darui's call, he begins to be drawn into the pot, just as Ino returns to her own body. As Kinkaku is being sealed, he laments how such fools could defeat him and his brother, but Darui retorts that even though gold and silver may shine brighter, a mass of copper coins can be worth more than one gold coin.

By nightfall, Tobi arrived at the battlefield and took both the Benihisago and Kohaku no Jōhei, each containing one of the brothers inside, intending to use their Nine-Tails chakra to help enact his Eye of the Moon Plan.

Trivia

 * literally means "Golden Horn", and shares the same name as the Kinkaku Force, suggesting that Kinkaku was its leader.
 * Both Kinkaku and his brother are likely based on two characters from the Chinese classic "Journey to the West". In this story, Kinkaku and Ginkaku are two demon king brothers, known as the and the.
 * Due to the brothers' ability to assimilate the Nine-Tails' chakra by eating its flesh, the Fourth Raikage suspected them to be distantly related to the Sage of the Six Paths.

Quotes

 * (To Darui) "Like they always say, 'silence is golden'. Words are the true source of all the world's ills… right Ginkaku?"