The tailed beasts (尾獣, bijū) are the nine titanic behaemoths that serve to drive the plot of the Naruto series. They are differentiated by the number of tails they have, ranging from one to nine. The tailed beasts are 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. The tailed beasts' chakra is coloured red.
According to some, the immense strength that the tailed beasts possess is tempered by their bestial nature, which restricts them from being intelligent enough to use it effectively, thus when the tailed beasts are sealed within humans, they are able to benefit from the knowledge of their hosts, giving them the ability to better utilise their powers. However, this was proven to be false, as the tailed beasts themselves are in fact sapient individuals with their own personalities and emotions, and because of their power, they were sought out by countless humans throughout the ages, and were usually treated as mere tools to be used or taken, a sentiment they absolutely detest. In addition, they are well aware of their origin and the state of the ninja world.
They also have the ability to communicate telepathically with each other and their jinchūriki, and possess several levels of consciousness. There is the initial level where the beast may appear in a habitat of sorts seemingly imprisoned in some way by whatever fūinjutsu that sealed them. The second level is where all the tailed beasts can convene, free of any restrictions and communicate with one another. The jinchūriki are also able to enter there, but in order to do so, they must be completely linked with their tailed beasts.
See also: Jinchūriki
In the beginning of ninja history, centuries before the founding of the ninja villages, there existed a god-like entity known as the Ten-Tails, which plagued the world until the Sage of the Six Paths defeated and sealed the beast within himself, making him the first jinchūriki. However, knowing that his death would release the Ten-Tails back into the world, the Sage used his ability, the "Creation of All Things", to divide its chakra into the nine tailed beasts, before using Chibaku Tensei to seal its body in what would become the moon. Some time after being created, the Sage gave each of the young tailed beasts a name and told them that they would always be together, even when separated. He also told them that one day, they would become one entity again with a different name as well as forms than they did at that time; when the time came for them to understand what true power was. Despite their close relation to one another, there is a significant amount of friction between them. One such cause was due to Kurama's belief that their strength was determined by their number of tails.
By the time of the formation of the shinobi villages, Hashirama Senju, the First Hokage, used his Wood Release techniques to capture and give several tailed beasts to the other shinobi villages as peace treaties, in order to stabilise the balance of power between them. However, after Hashirama's death, the villages had trouble containing the beasts themselves and they began to run wild, so the villages instead moved to seal the tailed beasts within humans. In order to ensure that the jinchūriki wouldn't turn traitor, it has been common practice to choose the jinchūriki from the village's Kage family, such as a sibling or a spouse. The strength of the jinchūriki would then be used to protect the village and be a living display of the Kage's power. Throughout history, very few people have ever gained full control over a tailed beast. Despite this, some have been able to use the power of the tailed beasts outside of actually becoming true jinchūriki. The legendary Gold and Silver Brothers became Kurama's pseudo-jinchūriki, as they were once devoured by it, but managed to survive by consuming some of its own normally-deadly flesh, becoming tinged with its chakra.
With the power of the Sharingan, Madara Uchiha was able to control the Nine-Tails and use it during his battle with Hashirama Senju. During the battle, however, control of the beast was wrested from him, and he was thought to be defeated at the Valley of the End. However it was later revealed that he had in fact survived the altercation, and obtained Hashirama's DNA — his true purpose for the encounter. Integrating Hashirama's DNA into his wounds, Madara awakened the Rinnegan shortly before the end of his natural lifespan. With it, he was able to summon the vessel of the Ten-Tails from the moon. However, using artificial means to expand his life, Madara was unable to carry out his plan to revive the Ten-Tails. As such he passed on this task to a young Obito Uchiha who had come to share his view on the world after Rin Nohara's death.
With the help of Akatsuki, by the time of the Fourth Shinobi World War, seven of the nine tailed beasts had been sealed into the statue. Later, all the beasts were resealed into their respective, reincarnated hosts which had been made into a personalised Six Paths of Pain. Irked by the slow progress of the plan, Tobi accompanied by the statue entered the battlefield to obtain the Benihisago and Kohaku no Jōhei which contained the Gold and Silver Brothers who were pseudo-jinchūriki of the Nine-Tails. Despite not having sealed the Eight and Nine-Tails entirely — only possessing portions of their power, Tobi decided to begin the plan as the Demonic Statue of the Outer Path undergoes a painful regeneration into the Ten-Tails. When Madara realised that the plan had begun without the Eight and Nine-Tails being absorbed, he attempted to rectify this. Despite Naruto and Killer B's attempt to destroy Demonic Statue while in mid-transformation, it successfully is restored into the Ten-Tails, albeit in an incomplete form.
The Tailed Beasts
Main article: Shukaku Shukaku (守鶴, Shukaku), more commonly known as the One-Tail (一尾, Ichibi), is a tailed beast that was last sealed within Gaara of Sunagakure. It has been captured by Deidara, then extracted and sealed by Akatsuki.
Main article: Matatabi Matatabi (又旅, Matatabi), more commonly known as the Two-Tails (ニ尾, Nibi), is a tailed beast that was sealed within Yugito Nii of Kumogakure. It has been captured by Hidan and Kakuzu, then extracted and sealed by Akatsuki. It was later resealed into a reincarnated Yugito during the Fourth Shinobi World War.
Main article: Isobu Isobu (磯撫, Isobu), more commonly known as the Three-Tails (三尾, Sanbi), is a tailed beast that was formerly sealed in Yagura of Kirigakure, after being sealed in Rin Nohara as part of Kirigakure's plan to attack Konohagakure. It has been captured by Deidara and Tobi, then sealed by Akatsuki. It was later resealed into a reincarnated Yagura during the Fourth Shinobi World War.
Main article: Son Gokū Son Gokū (孫悟空, Son Gokū), more commonly known as the Four-Tails (四尾, Yonbi), is a tailed beast sealed within Rōshi of Iwagakure. It was captured by Kisame Hoshigaki, then extracted and sealed by Akatsuki. Son was later resealed into a reincarnated Rōshi during the Fourth Shinobi World War.
Main article: Kokuō Kokuō (穆王, Kokuō), more commonly known as the Five-Tails (五尾, Gobi), is a tailed beast sealed within Han from Iwagakure. It has been captured, extracted, and sealed by Akatsuki. In the anime, Kokuō is indicated to have been one of the two tailed beasts that Akatsuki captured before the start of Part II. It was later resealed into a reincarnated Han during the Fourth Shinobi World War.
Main article: Saiken Saiken (犀犬, Saiken), more commonly known as the Six-Tails (六尾, Rokubi), is a tailed beast sealed within Utakata of Kirigakure. It has been captured by Nagato in the anime, then extracted and sealed by Akatsuki. It was later resealed into a reincarnated Utakata during the Fourth Shinobi World War.
Main article: Chōmei Chōmei (重明, Chōmei), more commonly known as the Seven-Tails (七尾, Nanabi), is a tailed beast sealed within Fū from Takigakure. It has been captured, extracted, and sealed by Akatsuki. In the anime, Chōmei is indicated to have been one of the two tailed beasts that Akatsuki captured before the start of Part II. It was later resealed into a reincarnated Fū during the Fourth Shinobi World War.
Main article: Gyūki Gyūki (牛鬼, Gyūki), more commonly known as the Eight-Tails (八尾, Hachibi), is a tailed beast sealed within Killer B of Kumogakure after Fukai, Fukai's uncle and Fukai's father failed before him.
Main article: Kurama Kurama (九喇嘛, Kurama), more commonly known as the Nine-Tails (九尾, Kyūbi), is a tailed beast currently sealed within Naruto Uzumaki of Konohagakure. The fox was first sealed into Mito Uzumaki after the battle at the Valley of the End, then into Kushina Uzumaki after Mito's death, before being sealed into Naruto when he was born.
Main article: Ten-Tails The Ten-Tails (十尾, Jūbi) is the primordial entity tied to the legend of the Sage of the Six Paths. Its chakra was divided into the nine tailed beasts and its body sealed into what would become known as the moon, by the Sage in his final moments of life. The Ten-Tails is considered to be the creator of the world, and the herald to its end should it ever be revived. Obito Uchiha's ultimate ambition, which was created and designed by Madara Uchiha, the Eye of the Moon Plan, is to capture and merge all nine of the tailed beasts' chakra back into the Ten-Tails' body, and become its jinchūriki and then 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.
- In the manga, before Taka began working with Akatsuki, Akatsuki was said to have seven tailed beasts. In the anime, when Taka is sent to capture Gyūki, the group has only six, the seventh missing beast being Saiken to make room for an additional anime-only arc.
- Several non-jinchūriki shinobi, such as Kisame Hoshigaki and the Fourth Raikage, have been said to hold chakra levels comparable to that of a tailed beast. In fact, the former has been given the moniker of Tailed Beast without a Tail (尾を持たない尾獣, O o Motanai Bijū; English TV "Tailless Tailed Beast").
- Madara has claimed that the power of his Susanoo is comparable to that of a tailed beast.
- In Naruto Shippūden 2: Bonds, it features a creature called the Zero-Tails. Despite having a numerical tail name, it is not an actual tailed beast and it has characteristics that are quite different from them.
- Among the tailed beasts, only Kurama has been shown to be subject to the Summoning Technique.
- The concept of a pseudo-jinchūriki was explored in an anime-exclusive arc, in which Sora was revealed to have had residual chakra from Kurama, collected after it rampaged Konoha, sealed into him. This happened before the introduction of the concept in the manga.
- A Kumogakure ninja once attempted to replicate the Gold and Silver Brothers' stunt with tentacle meat from Gyūki, but died instead. The brothers' success was attributed to a possible distant relationship with the Sage of the Six Paths.
- In the anime, the Four Celestial Symbols Men were also able to siphon Shukaku's power in order to revive their leader, Seimei.