The tailed beasts
The tailed beasts (尾獣, bijū) are nine giant demons that serve to drive the plot of the Naruto series. They are differentiated by the number of tails they have, with each possessing a number from one to nine. The tailed beasts are large, living forms of chakra, sometimes referred to as "Chakra Monsters" (チャクラのバケモノ, Chakura no Bakemono), giving them power that far outmatches most shinobi. However, this immense strength is tempered due to their bestial nature, which restricts them from being intelligent enough to use it effectively. When the tailed beasts are sealed within humans, they are able to benefit from the knowledge of their hosts, giving them the ability to speak and better utilize their powers. Akatsuki has been capturing the tailed beasts and their hosts, and as of the Fourth Great Shinobi World War possess seven of the nine beasts.
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History
In the beginning of ninja history, centuries before the founding of the ninja villages, there existed one demon, the Ten-Tailed Beast, that plagued the planet until the Sage of the Six Paths defeated and sealed the beast within himself, making him the first jinchūriki. On his deathbed, he divided the Ten-Tails' chakra into the nine other tailed beasts and sealed its body in the moon.
By the time of the formation of the shinobi villages, Hashirama Senju, the First Hokage, managed to capture and control some of them with his Wood Release techniques, and used them as peace treaties to the other great shinobi nations in order to stabilize the balance of power between them. After his death, however, the shinobi nations couldn't control these giant demons themselves and they began to run wild, so the nations instead moved to seal the tailed beasts within humans.
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The Tailed Beasts
One-Tailed Shukaku
The One-Tailed Shukaku (一尾の守鶴, Ichibi no Shukaku) is a tailed beast that was sealed within Gaara of Sunagakure since before his birth. It has been captured by Deidara, then extracted and sealed by Akatsuki.
Background
According to Madara Uchiha, the One-Tail first came into being in the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. Citizens of Sunagakure believed that "Shukaku," as the One-Tail came to be called, was a living ghost (生霊, ikiryō), a spirit of a corrupted Suna priest that turned into a demon. It was originally sealed inside a tea kettle, and then was placed within its first jinchūriki.
When Karura, the wife of Fourth Kazekage, became pregnant, her husband ordered Chiyo to seal Shukaku inside an unborn Gaara, but only after being removed from its second jinchūriki. Karura died as a sacrifice for the sealing process, and cursed all the people of Suna, including her husband, for what they had done. Apparently, one of Shukaku's former jinchūriki was the one who inspired the Third Kazekage to create the Iron Sand technique.
Appearance
Shukaku resembles a sand-colored tanuki with dark blue markings all over its face, body, and tail. It has a jagged, concave mouth, and its eyes' scleras are black with yellow irides that each contain a black four-pointed star with four small black circles that surround it.
Personality
Shukaku is intelligent, but also incoherent, giving it the demeanor of a drunkard, which fits well with the typical depictions of tanuki in Japanese folklore. Shukaku itself translates to "drunk" in Japanese. Like other tailed beasts, its innate rage and bloodlust influences its behavior. According to Gaara, Shukaku relishes the opportunity to kill anyone in sight, even more so during a full moon. Gaara knows how to control it sometimes, but most of the time it simply forces him to let it out.
Activity inside Gaara
As Shukaku's jinchūriki, Gaara has the ability to move and levitate sand at will. In addition, Shukaku protects him at all times with the Shield of Sand, regardless of his will (even self-inflicted injuries are prevented by the sand). He also suffers from lifelong insomnia, a side-effect of being Shukaku's jinchūriki. Whenever he fell asleep, Shukaku would eat away his personality, turning him into a monster.
When angry or in a state of bloodlust, Gaara can use the sand in his gourd to take on the form of a miniature Shukaku, or even create a giant copy of Shukaku's body. It is only when Gaara begins to take on Shukaku's form that he is allowed access to its wind element, such as Wind Release: Drilling Air Bullet. Gaara can even allow Shukaku to take on the full Shukaku form by going to sleep, but is left vulnerable, as his sleeping body is left unprotected on Shukaku's head.
Part I
Invasion of Konoha arc
During the Invasion of Konoha, Gaara transformed into his full Shukaku form during his fight with Naruto Uzumaki, who later summoned Gamabunta. When Gaara exposed himself on top of Shukaku's head and used the Feigning Sleep Technique, Shukaku took full control of its body and battled them. Shukaku's power was too much for Gamabunta to handle, resulting in Naruto using the Combination Transformation to take the form of a giant fox (the Nine-Tailed Demon Fox in the anime), which allowed Gamabunta to grab Shukaku in order for Naruto to punch Gaara in order to wake him up, which suppressed Shukaku's power.
Part II
Rescue Gaara arc
During Gaara's time as the Fifth Kazekage, Deidara and Sasori from the organization Akatsuki were assigned to capture Shukaku. After Deidara defeated Gaara in combat and took him to Akatsuki's lair in the Land of Rivers, Shukaku was forcefully extracted from Gaara, thus killing him. Gaara was resurrected through a combination of Chiyo's life-transferring technique and Naruto's chakra. Even though he is no longer the host of Shukaku, Gaara is still able to control sand.
Influence
Tanuki (狸) is the Japanese name for the raccoon dog. The tanuki has been renowned for its mischievous nature and abilities to shape-shift and bring good fortune. Shukaku has ties to several tanuki archetypes. One is the Bunbuku Chagama tale, where a tanuki sealed inside a tea kettle is then placed inside its first host. In the series, Shukaku was reported to have been sealed within a tea kettle. Some tales state of a shrine priest being a tanuki in disguise, which ties into how, early in the series, Shukaku was reportedly a corrupted Suna priest.
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Two-Tailed Monster Cat
The Two-Tailed Monster Cat (ニ尾の化け猫, Nibi no Bakeneko) is a tailed beast that was sealed within Yugito Nii of Kumogakure when she was two years old. It has been captured by Hidan and Kakuzu, then extracted and sealed by Akatsuki.
Background
According to Madara Uchiha, the Two-Tails first came into being near the end of the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the demon's chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. Like the One-Tailed Shukaku, many people believed that the Two-Tails was once a human that turned into a living ghost (生霊, ikiryō). The Two-Tails eventually fell into the possession of Kumogakure and sealed into a two-years-old Yugito Nii. She was placed into a detestable training program in order to learn to control the Two-Tails' power.
Appearance
The Two-Tails resembles a bakeneko covered in wild blue flames. Its eyes are like an odd-eyed cat, with a right yellow eye and a left green eye, only without pupils.
Activity inside Yugito
As the Two-Tails' jinchūriki, Yugito had the ability to transform into the monster cat, giving her access to its strength and its ability to breathe fireballs from its mouth without losing much control.
Part II
Hidan and Kakuzu arc
Soon after her introduction, Yugito was captured by two Akatsuki members, Hidan and Kakuzu, although it is unknown who was specifically assigned to capture her. Despite luring her two pursuers into a closed space, sealing the exits, and transforming herself into the Two-Tails, Yugito was overpowered and rendered unconscious by the two Akatsuki members. Zetsu later arrived to take her off their hands, and she later died as a result of having the tailed beast extracted from her.
Influence
Cats are the common species throughout the world, and stories of bakeneko (化け猫, monster cats) are popular throughout Japan. In myth, when a cat reaches a certain age, it grows larger, and its tail becomes longer and forks in two, and is then called a nekomata (猫俣, forked-cat). Reportedly large in size, these cats are said to have the ability to manipulate the dead like puppets, and have been associated with strange fires and occurrences. This may be related to the monster cat's nickname and its fire-breathing abilities.
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Three-Tailed Giant Turtle
The Three-Tailed Giant Turtle (三尾の巨大亀, Sanbi no Kyodaigame) is a tailed beast that was formerly sealed in Yagura of Kirigakure, but was extracted for unknown reasons. It has been captured by Deidara and Tobi, then sealed by Akatsuki.
Background
According to Madara Uchiha, the Three-Tails first came into being near the end of the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the demon's chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts.
At some point in the past, the Three-Tails fell into the possession of Kirigakure and was sealed within Yagura, the Fourth Mizukage. It was later extracted from its host for some reason, and escaped into the wild. Because it did not have a jinchūriki, it was not intelligent enough to effectively utilize its great strength, instead being reduced to animal instincts.
Appearance
The Three-Tails primarily resembles a turtle, but with a crab-like shell and three shrimp-like tails. It has no hind-legs, only a pair of fore-legs. Its right eye is constantly closed, indicating some sort of injury, and because of this, it is particularly vulnerable to attacks directed at its left eye.
Abilities
Other than being a very fast swimmer despite its size, the Three-Tails' abilities were not seen in the manga. Tobi suggested that Kisame would have been a better choice for capturing the beast, given its affinity for water. In the anime, its abilities were greatly elaborated upon, many of which dealt with its size: it could roar to repel attacks; it could produce a large tidal wave that spread away from it in all directions; it could strike with any of its three spiked tails to break through most defenses. Its skin was resistant to attack in a similar fashion.
Of the beast's more specialized abilities, it could produce a hallucinogenic mist that exploited the victim's insecurities and forced the victim to face them. It could also shoot white, Menacing Ball-like shockwaves. When it swallowed something, thousands of "mini-clones" of itself would attack what it had eaten within its gut, presumably to facilitate digestion.
Part II
Three-Tailed Beast arc
In the anime, Orochimaru instructed Kabuto Yakushi and Team Guren to take a young boy named Yūkimaru to a lake. After they arrived, Kabuto forced Yūkimaru to release all of his chakra, which caused the Three-Tails to begin to surface from the lake. With Guren's help, the beast was completely revealed, and they attempted to capture it. Their attempts proved insufficient, however, and the beast created a large tidal wave to wash its attackers away.
The tidal wave gained the attention of a nearby group of Konohagakure ninja, who tried to use Four-Corner Sealing Barrier to permanently trap the beast in its own dimension. Just as the sealing began to work, the Konoha ninja were interrupted by Guren, which prompted the beast to attack them all. Yūkimaru was able to calm the beast down temporarily, but, after he became tired, the Three-Tails turned its attention to him. Guren and Naruto Uzumaki came to his defense, but were swallowed in the process. With the help of their allies on the outside, they were able to escape, and the Konoha ninja tried once more to seal the beast.
Just when the sealing was almost complete, Yūkimaru, angered by the apparent death of Guren, empowered the beast to break free of its restraints. The Three-Tails went on a rampage, attacking everyone nearby and crushing Nurari, Kigiri, and Kihō. Its attempts to attack Yūkimaru, however, had no effect. It was only through the use of the Wind Release: Toad Oil Flame Bullet that the beast was driven away. The sealing attempt was left to ANBU members, and the remaining Konoha ninja returned home. Deidara and Tobi of Akatsuki soon found these ANBU members and disposed of them.
The beast's capture took place much earlier in the manga (at the start of the Hidan and Kakuzu arc), but played out in much the same way as in the anime. Tobi and Deidara confronted the beast, to which it responded by beginning to chase Tobi. With the Three-Tails distracted, Deidara molded an explosive clay fish in an attempt to capture it. It was unclear if this marked the end of the battle, as the remainder of the battle went unseen. As the two towed the Three-Tails to the Akatsuki's lair after the battle, Tobi gloated at bringing the Three-Tails down with his special jutsu, but Deidara thought otherwise. It was later sealed in the sealing statue.
Influence
Turtles are often used as the base design for sea monsters in Japanese folklore. The Three-Tails' design in particular was conceived as a result of the series creator, Masashi Kishimoto's, interest in monsters, yōkai, and kaijū, mixing together various elements of those types of creatures to create a monster with a turtle's body and a shrimp's tail with a crab-looking figure.
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Four-Tailed Monkey
The Four-Tailed Monkey (四尾の猿, Yonbi no Saru) is a tailed beast sealed within Rōshi of Iwagakure. It has been captured by Kisame Hoshigaki, then extracted and sealed by Akatsuki.
Background
According to Madara Uchiha, the Four-Tails came into being near the end of the waning days of the Sage of the Six Paths' life; to prevent it's resurgence, the Sage split up the demon's chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. The Four-Tails eventually fell into the possession of Iwagakure and was sealed into Rōshi at a young age.
Activity inside Rōshi
As the Four-Tails' jinchūriki, Rōshi had the ability to use its power of Lava Release, a combination of fire and earth the likes of which have rarely been seen outside of kekkei genkai.
Part II
Hunt for Itachi arc
After an unseen and difficult battle with Kisame Hoshigaki, Rōshi was somehow defeated and captured by him. Kisame had difficulty capturing Rōshi because of the Four-Tails' ability of Lava Release. The Four-Tails was later extracted and sealed, leading to Rōshi's death.
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Five-Tailed Dolphin Horse
The Five-Tailed Dolphin Horse (五尾のイルカ馬, Gobi no Irukauma) is a tailed beast sealed within Han from Iwagakure. It has been captured, extracted, and sealed by Akatsuki.
Background
According to Madara Uchiha, the Five-Tails first came into being in the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. The Five-Tails eventually fell into the possession of Iwagakure and was sealed into Han.
Appearance
The Five-Tails primarily resembles a white horse, but its head is based off of a dolphin with two long and short horns.
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Six-Tailed Slug
The Six-Tailed Slug (六尾の蛞蝓, Rokubi no Namekuji) is a tailed beast sealed within Utakata of Kirigakure. It has been captured by Nagato in the anime, then extracted and sealed by Akatsuki.
Background
According to Madara Uchiha, the Six-Tails came into being in the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. The Six-Tails eventually fell into the possession of Kirigakure and was sealed into Utakata.
According to the anime, at some point before his appearance, Utakata's master, Harusame, tried and failed to remove the Six-Tails from within Utakata to save his student from being a living weapon for his village. Utakata, however, having not heard what his master had said to him, later came under the assumption after the incident that his master had tried to kill him. This failed removal resulted in Utakata transforming into the Six-Tails and killing Harusame.
Appearance
The Six-Tails resembles a white, bipedal slug with small arms. Its entire body is covered in a slimy substance.
Part II
Six-Tailed Beast arc
In the manga, the Six-Tails' capture is not seen. In the anime, before Taka began working with Akatsuki, Akatsuki was said to have seven tailed beasts. When Taka is sent to capture the Eight-Tails, the group has only six, the seventh missing beast being the Six-Tails. Utakata's capture is the subject of its own arc, though little is actually seen of the Six-Tails outside of Utakata's transformations. Utakata is captured by the Six Paths of Pain at the end of the arc and the Six-Tails is extracted from his body, resulting in his death.
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Seven-Tailed Horned Beetle
The Seven-Tailed Horned Beetle (七尾のカブトムシ, Nanabi no Kabutomushi) is a tailed beast sealed within Fū from Takigakure. It has been captured, extracted, and sealed by Akatsuki.
Background
According to Madara Uchiha, the Seven-Tails first came into being in the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. The Seven-Tails eventually fell into the possession of Takigakure and was sealed into Fū, but was captured and extracted by Akatsuki.
Appearance
The Seven-Tails resembles a blue, armored kabutomushi, with six of its seven tails resembling green insect wings, along with the seventh tail, all growing from the end of its abdomen.
Influence
The kabutomushi (カブトムシ, rhinoceros beetle) is among the largest of beetles found in the world. They are also among the strongest animals on the planet in relation to their own size. Its penchant for fighting other males of the species has made them a popular gambling subject in Asia. Beetles are characterized by a hard exoskeleton and forewings, which creates a flexible armored defense. The forewings are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings that are used for that purpose. It is also frequently depicted in popular media as a common cartoon character for various uses.
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Eight-Tailed Giant Ox
The Eight-Tailed Giant Ox (八尾の巨牛, Hachibi no Kyogyū) is a tailed beast sealed within Killer Bee of Kumogakure.
Background
According to Madara Uchiha, the Eight-Tails came into being near the end of the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the demon's chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. The Eight-Tails eventually fell into the possession of Kumogakure and was sealed into Killer Bee.
Appearance
The Eight-Tails resembles an ushi-oni with three long horns and a short left horn. It has an upper-body structure of a human, but has no hind-legs. Its 'tails' are really eight cephalopod arms of an octopus, and according to Killer Bee, its tails are able to eventually grow back even after they have been cut off.
Personality
Killer Bee and the Eight-Tails appear to be able to speak to each other in a much more relaxed state than Naruto Uzumaki and the Nine-Tailed Demon Fox. For example, when Naruto has a conversation with the Nine-Tails, the latter is in a cage with a special seal keeping it from taking over Naruto. As Killer Bee is one of the few people who has total control over his own tailed beast, he and the Eight-Tails can talk without such restraints, with Killer Bee even sitting on top of its muzzle. The Eight-Tails is shown to get easily annoyed with Killer Bee's crazy antics; however, that is somehow shown to be comical.
However, despite Eight-Tails' friendly relationship with Killer Bee, the Eight-Tails, like the other beasts, main goal is self preservation. For example, it was more than willing to be released and destroy Kisame Hoshigaki despite Sabu and Ponta being close by. However, behind the brutal appearance the Eight-Tails is shown to have a good analytical ability, as he told Killer Bee that if he left Ponta and Sabu and run in the opposite direction Kisame and the water will follow him and they (Sabu and Ponta) will be free.
Activity inside Killer Bee
As the Eight-Tails' jinchūriki, Killer Bee can transform himself into the Eight-Tails and can access its high-level chakra without losing control. Killer Bee is one of the two jinchūriki who has been known to be able to fully control his tailed beast's powers, the other being Yagura. It has been shown to fire an attack similar to the Four-Tailed Fox Menacing Ball, but with much greater force. Killer Bee is also able to use the Eight-Tails to block his chakra to break illusions, even ones cast from a Mangekyō Sharingan. Killer Bee can also create ink because of the octopus nature that his tailed beast resembles.
Part II
Hunt for the Eight-Tails
When Taka arrived at Kumogakure in an attempt to capture Killer Bee, he battled them to the point of annoyance. With his great control over his demon, Killer Bee transformed himself into the Eight-Tails, and proceeded to terrorize Taka. As the Eight-Tails attacked, Suigetsu commanded a wave of water, attempting to defeat it. The Eight-Tails understood that Suigetsu had the advantage given that they were surrounded by water, so it then charged a huge ball of chakra and fired it at Suigetsu, defeating him.
Later, Sasuke Uchiha activated his Mangekyō Sharingan and released Amaterasu on the Eight-Tails and it fell into pain by its flames. As one of its tails was about to fall on Karin, Sasuke cut it with Chidori Sharp Spear. Killer Bee disguised himself as the cut part of the tail and escaped. Killer Bee was then seemingly captured by Taka and was given to Madara Uchiha. Killer Bee's brother, the Fourth Raikage, swore that Akatsuki would pay for what they had done.
It was later revealed that Killer Bee faked his capture. After Taka left, he and the Eight-Tails left the lake and Killer Bee took this opportunity to take a "vacation" from being a guardian. The Eight-Tails commented that a new era is coming, and Killer Bee thinks its going to be his singing career.
Five Kage Summit arc
As Kisame attacks Killer Bee, Eight-Tails demands Bee to let him out. However, Bee reminds him that he would just kill Sabu and Ponta in the process of protecting itself. With this, Eight-Tails begrudgingly let Bee use the Seven-Tailed version 2 mode, as well as giving Bee advice during the battle. However, as Kisame knocks Killer Bee out, Eight-Tails yells at him to wake up, worried as both Bee and it were nearly out of chakra. Kisame then prepared to finish the battle as the Raikage arrived and helped Bee kill "Kisame".
Fourth Shinobi World War arc
As Naruto Uzumaki and Yamato entered Land of Lightning, in the Allied Shinobi Forces's efforts to keep the jinchūriki away from Akatsuki, they were attacked by a giant squid. Killer Bee in his full Eight-Tails forced the squid back and saved the ship. Upon seeing it, Naruto realized that the Eight-Tails and Bee were the "octopus" he's been looking for to guide him to control the Nine-Tailed Demon Fox.
Influence
In Japanese folklore, an ushi-oni (牛鬼, ox ogre) is a massive, brutal sea-monster with the horned head of a bull and the body of a sea animal, like an octopus or a crab. It lives off the coasts of Japan and attacks fishermen.
An ushi-oni appears as protective symbol in the Ushi-oni-matsuri, which is held in late July in Uwajima of Ehime Prefecture. Like the dragon dancers at a Chinese New Year celebration, an ushi-oni is represented with a huge, multiple-person costume with a cloth body and a carved, painted head held upon a pole. It has a sword for a tail, and is thought to drive away evil spirits.
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Nine-Tailed Demon Fox
The Nine-Tailed Demon Fox (九尾の妖狐, Kyūbi no Yōko) is the most powerful out of all nine of the tailed beasts; a single swipe from just one of its nine tails can create tsunamis and flatten mountains. When the Nine-Tails attacked Konohagakure, Minato Namikaze, the Fourth Hokage, sacrificed his own life by sealing it within his newborn son, Naruto Uzumaki.
Background
The Nine-Tails first came into being in the waning days of the Sage of the Six Paths' life; to prevent the Ten-Tailed Beast resurgence, the Sage split up its chakra into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. Over the centuries, the Nine-Tails gained a reputation as an age-old natural disaster, appearing at random to attack areas where human malice has collected and festered.
Many decades ago, when Madara Uchiha defected from Konoha, he used his Mangekyō Sharingan to take control of the Nine-Tails, and used it to help him fight against Hashirama Senju, the First Hokage, to exact his revenge. The battle was so great that it tore the earth apart and created the Valley of the End. Despite being in control of the Nine-Tails' power, Madara was defeated and was believed to have died.
Twelve years before the start of the series, the Nine-Tails attacked Konoha. Although Madara denied that he had summoned it to destroy the village and claimed that its attack had been a natural occurrence, Itachi Uchiha and Minato both said that the Nine-Tails was under Madara's control at the time. During the attack, the Nine-Tails decimated many shinobi that tried to repel it. Minato, riding atop of Gamabunta, was able to defeat the Nine-Tails by sealing it within Naruto.
In the anime, it was revealed that the Nine-Tails had left behind large amounts of its chakra during the attack. Kazuma collected and sealed the chakra within his own son, Sora, hoping to make use of its power for his own agenda.
Appearance
Although the Nine-Tails primarily resembles a demonic kitsune with orange fur and blood-red slitted eyes, it also possesses the upper-body structure of a human, complete with opposable thumbs on its pawed hands. Out of all the tailed beasts, the Nine-Tails' form is closest to the form of the Ten-Tails.
Personality
The Nine-Tails is malevolent, sadistic, cunning, and sarcastic, but it does have a distinct sense of honor and pride, and possesses a loathing respect for Naruto and Minato. At first, the Nine-Tails wanted to kill Naruto, but it soon realized that it shares the same fate as Naruto as long as it is sealed within him; so it has no choice but to cooperate with Naruto or it will die along with him. It will go to great lengths to preserve its own life, as shown when it forces its chakra into Naruto whenever his life is in danger. Later in Part II, the Nine-Tails became very angry and contemptuous at Naruto when he rejected its chakra, although this was merely the rage of missing the opportunity to usurp control over Naruto's mind and body, which would have weakened the seal. However, it will back down if Naruto threatens to harm himself.
The Nine-Tails has a deep hatred for the Uchiha clan and their Sharingan, likely because of the many times Madara manipulated it in the past. It even remarked that Sasuke Uchiha is a lot like Madara because of his power of the Sharingan. The Nine-Tails actually knows the truth about the Uchiha clan and about Naruto, but it appears that it has no intention of telling what it knows.
Activity inside Naruto
As the Nine-Tails' jinchūriki, Naruto is gifted with its mass amount of chakra and stamina, immense strength, increased speed, accelerated healing, and, at times, an almost impenetrable chakra shield. The Nine-Tails' chakra allows Naruto to perform his signature jutsu, Shadow Clone Technique, seemingly without limit. He is even able to summon Gamabunta, a feat that is normally Kage-level as the technique requires an amount of chakra proportionate to the size of the summoned creature.
Although the Nine-Tails' chakra naturally mixes with Naruto's own, Naruto can forcefully tap into its chakra reserves. After training with Jiraiya, he learned to request some of the Nine-Tails' chakra for his own use. Alternatively, and what has become the more common method over time, he can give into his anger or frustration, allowing the Nine-Tails to force its influence upon him. Depending on how much of its chakra he gains, Naruto can lose control of his senses, devolving into an animal that attacks anything within reach, as well as damaging his body with the Nine-Tails' chakra, slowly shortening his lifespan. For these reasons, Naruto learned to exercise more control over the Nine-Tails' chakra.
A number of methods have been devised to break the Nine-Tails' influence over Naruto: Yamato can use the Hokage-style Sixty-year-old Technique - Kakuan Entering Society with Bliss-bringing Hands, which was facilitated by the necklace Naruto wore before its destruction; a Chakra-Suppressing Seal can be applied to Naruto's body; or an Uchiha with a mature enough Sharingan can enter Naruto's subconscious and force the Nine-Tails to recede. The most effective of measures, however, is Naruto simply limiting his use of the Nine-Tails' chakra and not allowing his anger to get the better of him.
According to Gerotora, the Nine-Tails' power consists of two parts: its chakra and its will. He explained that whenever Naruto draws out the Nine-Tails' chakra, its will comes along with it. The Nine-Tails' will itself contains a mass amount of hatred, and it will relentlessly try to control Naruto whenever given the chance. To control its power, Naruto must have his own will and heart both very strong and free of hatred, in order to seperate the Nine-Tails' will from its chakra completely.
The Seal
This is the seal that imprisons the Nine-Tails within Naruto. The Dead Demon Consuming Seal is composed of the Eight Trigrams Sealing Style, which allows Naruto to tap into the Nine-Tails' chakra reserves in times of need. Jiraiya later revealed that, when Minato had sealed the Nine-Tails within Naruto, he had split its chakra in two, the Yin and Yang. Minato sealed the Yang half within Naruto with the Eight Trigrams Sealing Style, and sealed the Yin half with the Dead Demon Consuming Seal, thus making it inaccessible to Naruto.
Whenever Naruto and the Nine-Tails converse, it occurs within Naruto's subconscious, which is depicted as a basement of a boiler room or a sub-level of a power plant, with pipes running across the ceiling and the floor being flooded over with water. The water represents the Nine-Tails' chakra that leaks out of the seal and is channelled into Naruto's chakra system; its level indicates how much of its chakra is being drawn out. On the entrance gate of the Nine-Tails' cage, there is a parchment of paper that says "seal" (封), which serves as a 'lock' to keep the Nine-Tails in.
The seal itself naturally weakens over time, something Minato created the key on the abdomen of the scroll toad Gerotora, to remedy. Gerotora explained that if the Nine-Tails' will is stronger than Naruto's while the seal is weak, the seal will break and the Nine-Tails will be released. Gerotora also explained that during Naruto's training, Jiraiya would usually use the key to suppress the Nine-Tails when necessary, but Jiraiya instead used it to weaken the seal for just a short time, to try teaching Naruto to filter out the Nine-Tails' will when he tapped into its chakra, but it instead unleashed the four-tailed transformation. As the seal weakens, Naruto's transformations occurs much quicker and with greater intensity, often against his own will. As seen during Naruto's Part II training sessions, even the slightest amount of frustration on Naruto's part allows the Nine-Tails' chakra to leak out of the seal, which will then rapidly progress to his four-tailed form, or onwards.
The seal also has a final safeguard to prevent the Nine-Tails from being released. Minato made it so that, if Naruto ever transformed into his eight-tailed form, Minato would appear in his subconscious in order to prevent the seal from being completely broken. Furthermore, Minato can restore the seal to its normal state, but he stated that he can only do it once.
Part I
Land of Waves arc
Naruto was not made aware of the Nine-Tails' presence within him until twelve years after its sealing. He first made use of its chakra during his battle with Haku. Believing Haku to have killed Sasuke, Naruto gave into his anger and entered his initial jinchūriki form in order to defeat Haku.
Chūnin Exam arc
Naruto did not realize that this was the Nine-Tails' chakra until he was later taught to take advantage of it by Jiraiya. To force Naruto to call upon the Nine-Tails' chakra, thus enabling him to use the Summoning Technique, Jiraiya threw Naruto off of a cliff. To save himself, Naruto entered his subconscious and met with the Nine-Tails for the first time. Immediately, the Nine-Tails wanted to devour Naruto, but it couldn't because of the seal that kept it within its cage. Naruto then, showing great courage, demanded some of its chakra as 'rent' in order to save them both, and the intrigued Nine-Tails complied, allowing Naruto to summon Gamabunta.
The Nine-Tails then kept quiet till Naruto battled Neji Hyūga in the first match of the final round. After Neji used his Eight Trigrams Sixty-Four Palms to block Naruto's chakra points, Naruto called upon the Nine-Tails for chakra. Without hesistation, it gave him enough chakra to force his chakra points to open and gave Neji, with his Byakugan activated, a glimpse of itself. With the help of the Nine-Tails' chakra, Naruto was able to defeat Neji.
Invasion of Konoha arc
During the battle with Gaara in his full Shukaku form, Naruto and Gamabunta both did a Combination Transformation technique to take the form of a giant fox (the Nine-Tails itself in the anime). As the battle continued, Naruto called upon the Nine-Tails again for chakra in order to awaken Gaara, and once again, it did so without hesistation.
Search for Tsunade arc
Later, when Kabuto Yakushi severed Naruto's heart muscles and the neighboring chakra system, the Nine-Tails was unable to heal the damage. While Tsunade tried to save Naruto, the Nine-Tails noticed that its power was fading as its surroundings grew darker and darker. It, like Naruto, had a near death experience, something it was slow to recognize. Fortunately, Naruto and, through him, the Nine-Tails, were saved by Tsunade.
Sasuke Retrieval arc
While Naruto battled Sasuke at the Valley of the End, Sasuke pierced a fatal wound on Naruto's right shoulder with his Chidori, but the Nine-Tails quickly gave Naruto enough chakra to enter his initial jinchūriki form and healed his large wound almost instantly, and with that, Sasuke saw the image of the Nine-Tails for the first time. As the battle continued, the Nine-Tails gave Naruto more chakra to attain the one-tailed transformation, something the Nine-Tails indicated that he should be grateful for.
Part II
Rescue Gaara arc
During his battle against the Akatsuki member Deidara, which turned out to be a Clay Clone, Naruto slipped into his two-tailed form out of anger at Gaara's death. When he was about to attack Kakashi Hatake, the latter placed a special seal tag given to him by Jiraiya on Naruto's forehead, restoring him back to normal.
Sasuke and Sai arc
Later, when his three-tailed form was proven insufficient in a fight against Orochimaru, Naruto gave into the Nine-Tails and entered his four-tailed form. The Nine-Tails gained control of his senses and began to attack everything that was around him, including both Orochimaru and Sakura Haruno. After its influence was suppressed by Yamato, he told Naruto how the four-tailed form had caused him to attack Sakura, someone that he cares about. Naruto resolved not to use the Nine-Tails' power again.
Soon afterwards, when Naruto met Sasuke again for the first time in years, the Nine-Tails tried to offer Naruto some of its strength. He refused, but before it could put up much of a fight, Sasuke, with his Sharingan activated, appeared within Naruto's subconscious. Surprised, the Nine-Tails commented that Sasuke's chakra is more ominous than its own, and that he is just like Madara Uchiha. Sasuke forced the Nine-Tails back into its cage, but before it was completely suppressed, the Nine-Tails warned Sasuke not to kill Naruto, telling him that he would only live to regret it. It saw little activity after that, surfacing within some of Naruto's shadow clones that had grown frustrated with the wind element training.
Twelve Guardian Ninja arc
In the anime, the Nine-Tails reacted to its leftover chakra that was stored within Sora. As Naruto in his three-tailed form battled Sora in his four-tailed form, the Nine-Tails started to force Naruto to accept its power, but he was able to keep the Nine-Tails from taking control of his body as he stabbed his leg and threatened the beast to back off. It begrudgingly pulled back, but it managed to take back all of its chakra from Sora.
Invasion of Pain arc
Later, when Naruto tried to learn senjutsu, the Nine-Tails prevented Fukasaku from fusing with Naruto, wanting Naruto to use its chakra instead of senjutsu chakra. It was given an opportunity to appear during Naruto's battle with Pain. After Pain appeared to have killed Hinata Hyūga, Naruto slipped into his six-tailed form, which the Nine-Tails used to its advantage by destroying the First Hokage's Necklace.
When Naruto was captured by Pain's Chibaku Tensei technique, the Nine-Tails tempted Naruto to give his heart to it so that it could destroy everything that was causing Naruto pain, thus distorting the seal to the point where the eight-tailed form was released. Before it could convince him to completely remove the seal, however, the spirit of Minato appeared in Naruto's subconscious to stop him. Enraged, the Nine-Tails tried its best to kill Minato for revenge, but Minato ignored it, soon afterwards restoring the seal to its original strength. Once Pain was defeated, Naruto confronted Pain's base mind, Nagato, and was able to simultaneously use senjutsu chakra and the Nine-Tails' chakra, combining the two different pupil appearances.
Fourth Shinobi World War arc
As Naruto is given the key to the seal from Gerotora, Gerotora and Fukasaku mention that Nine-Tails will no doubt use this oppurtunity to take control of Naruto's body and be free.
Influence
A kitsune (狐, fox) is a well-known character in Japanese folklore, and is the influence behind not only the Nine-Tails, but many other reincarnations in modern Japanese culture. It likes to play pranks on people, and, on occasions, transforms itself into a beautiful woman in order to seduce men (obviously the inspiration for the Sexy Technique). However, kitsune are known to keep their promises, a trait Naruto has; his ninja way is to "never go back on [his] word". It is also noted that, every time Naruto loses control and is overwhelmed by the Nine-Tails' chakra, he gains another 'tail' of chakra. This stems from the belief that the more tails a kitsune has, the more powerful it is, with nine tails being the limit.
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Ten-Tailed Beast
The Ten-Tailed Beast (十尾, Jūbi) is the original, primordial demon of the Naruto universe. All nine of the tailed beasts are but portions of chakra divided from the Ten-Tails. Madara Uchiha's ultimate goal, the Moon's Eye Plan, is to capture and merge all nine of the tailed beasts back into the Ten-Tails, and become its jinchūriki to cast the reflection of his Sharingan on the moon, casting a genjutsu known as the Infinite Tsukuyomi which will put the entire world under his control.
Background
Centuries before the founding of the hidden villages, the Sage of the Six Paths saved the world from the Ten-Tails. He managed to subdue the beast and sealed it within his own body, becoming what could be considered the first jinchūriki. However, this offered merely a temporary solution to the menace; in the event of his death, the seal would dissolve and the Ten-Tails would once again be unleashed upon the world. Knowing this, the Sage searched for a more permanent solution. Ultimately, the Sage succeeded by dividing the Ten-Tails' chakra into the nine monstrous entities that would later become known as "tailed beasts" and scattering them throughout the world. As a final precaution the Sage, using his Chibaku Tensei jutsu, entombed the physical remains of the Ten-Tails within a colossal stone prison and hurled it into the heavens, creating the moon.
Appearance
So far, the Ten-Tails has only been seen once, in silhouette, but the form of its body seemed to be closest to that of the Nine-Tailed Demon Fox's body. Also, it appeared to have only one eye, which had four Rinnegan-like concentric circles, with nine Sharingan-like tomoe in the three circles closest to the pupil.
Abilities
As the fusion of all nine tailed beasts, the Ten-Tails is said to possess massive and overwhelmingly foul chakra that is potent enough to bring total despair and destruction to the world. The astonishing feat of not only successfully sealing the Ten-Tails, but also suppressing it, made the Sage a god-like hero throughout the shinobi world.