Naruto Uzumaki's Jinchūriki Forms

Naruto Uzumaki is the third jinchūriki of the Nine-Tailed Demon Fox. He is gifted with its enormous supply of chakra and stamina, accelerated healing (recovering from minor injuries within a few seconds to major injuries within a day) and depending on the amount of the Nine-Tails' chakra he's using, Naruto is also given an increase in strength, speed, along with an increase in his healing factor to such levels that he recovered from a Chidori strike in mere seconds and, at times, he is granted a nearly impenetrable chakra shield. Naruto had a unique access to the Nine-Tails' chakra, due to the seal that his father, Minato Namikaze, the Fourth Hokage, placed on him. Minato stated that he sealed the Nine-Tails' Yang chakra within Naruto because he believed that Naruto would someday control its power to battle Madara Uchiha.

Initial Jinchūriki Form
By simply tapping into the Nine-Tails' chakra, Naruto's body begins its initial transformation. The first signs of this are his eyes: his pupils become slitted, and his eyes will change from blue to red. Following this, his nails and canine teeth grow longer and sharper and his blonde hair will grow longer and spikier, as it stands on end. Naruto's whisker marks will also widen and thicken, adding to his feral appearance. While he can still stand on his own two feet, Naruto can move at greater speeds by manoeuvring on all fours in a manner that looks similar to the Four Legs Technique used by the Inuzuka clan. Depending on how much of the Nine-Tails' chakra was unleashed, it was capable of glowing around his body in an untamed way, similar to fire. Until he achieved the Nine-Tails Chakra Mode, it was the only form which resembled flames.

At first, Naruto could only reach this state through sheer rage or if his life was in imminent danger, but after training with Jiraiya, Naruto learned how to contact the Nine-Tails and demand some of its chakra. Even though this was the weakest state of his jinchūriki forms, it still increased Naruto's physical strength (he was able to stop a massive snake going at incredible speeds), and its healing rate was able to regenerate his right shoulder and lung, pierced by Sasuke's Chidori. This form also increased his speed to such levels that nothing short of a fully matured Sharingan was able to track his movements. He could also use the chakra as a shockwave, sometimes merely using a roar or thrusting his fist out to send a rush of energy at his opponent.

When Naruto encountered Nagato face to face, he was shown to be able to simultaneously fuse his initial jinchūriki and Sage Mode forms together. His eyes took on the combined appearance of a mixture of them both. The exact capabilities of that form are unknown, but it was enough to completely resist Nagato's control of his Chakra Disruption Blades when it impaled Naruto.

One-Tailed Form
During Naruto's battle with Sasuke at the Valley of the End, the Nine-Tails granted Naruto more of its usual chakra, in which it began to envelop Naruto's body as a bubbling chakra-construct, taking on the shape of a one-tailed fox, which Jiraiya referred to as the. All the physical traits of the initial jinchūriki form were present and slightly altered, including the black rings that surround the more berserk-looking eyes. In this form, Naruto could use his elongated, sharpened claws instead of his fists, and run at greater speeds on all fours, making him more like a beast. The chakra itself is noticeably denser than the chakra in the Initial Jinchūriki Form, going from a gaseous state to a boiling liquid state.

Naruto's most powerful weapon in this state was the demon fox shroud itself, and it appeared to have a mind of its own; when a strike that was meant for Sasuke missed, the chakra itself stretched off of Naruto's arm and managed to hit Sasuke before he had time to react. Since the chakra was sentient, it was extremely difficult, if not impossible, to predict, as Naruto was followed with the Sharingan, but the chakra was not. The shroud granted Naruto some measure of protection, as it could withstand attacks like the Fire Release: Great Fireball Technique. Naruto could also use the shroud's chakra arms and tail as grappling hooks to either grab onto objects or enemies from great distances, and use it as a shell to help him create a Rasengan without the help of his shadow clones. However, the shroud was not without its drawbacks; after Naruto used his left arm for a number of attacks against Sasuke, it was left numb from overuse and the constant damage of the Nine-Tails' chakra on his body.

After the timeskip, Naruto had shown great control over and ease entering it, able to stay conscious in using this form. His speed and strength in this form also increased to the point where he was able to blitz Orochimaru who couldn't move fast enough to counter, and send him crashing through the forest behind Tenchi Bridge with a single blow.

Two-Tailed Form
After catching the Akatsuki member Deidara, only to discover it was a Clay Clone, Naruto's frustration and anger at Gaara's death caused him to slip into his two-tailed form. His physical characteristics matched the first two forms, but his red eyes and canines grew larger, and his lips acquired a black outline similar to the Nine-Tails'. The amount of chakra produced by the two-tailed form was so powerful that even Naruto's shadow clones doubled over in pain.

While in this state, Naruto was still in control of his body, though to what extent is unknown. In the anime, he punched a tree, destroying it and a long line of trees behind it. He later attempted to attack Kakashi Hatake, who placed Jiraiya's seal tag upon Naruto's forehead, bringing him back to his normal self.

Three-Tailed Form
After Orochimaru revealed himself to Team Kakashi, and baited Naruto with news of Sasuke, Naruto went on a rampage, first attacking Orochimaru and progressing from a one-tailed to a three-tailed form in doing so. The three-tailed form looks similar to the two-tailed form, but with the Nine-Tails' features becoming even more pronounced. This was the strongest tailed form that Naruto could reach without losing control.

In this form, the chakra it produced was caustic, such that the air around Naruto began to sting others; and with the demon fox shroud's increased protection and attack power, Naruto's roar has the power to create a powerful sphere of destruction, capable of destroying the Tenchi Bridge. In Naruto Shippūden 2: Bonds, while fighting the Zero-Tailed Masked Leech, Naruto was able to use the demon fox shroud to mimic arms and wings for semi-flight.

Four-Tailed Form
When Orochimaru further taunted Naruto about Sasuke, Naruto, in a fit of fury and anger, grew the fourth chakra tail, but in doing so, he had slipped into the Nine-Tails' grasp. The Nine-Tails' chakra began to burn its way through Naruto's entire body, completely destroying his skin while rapidly healing it at the same time. Naruto's body was eventually covered in a mix between the Nine-Tails' chakra and his own blood. Everything from his face to his chakra tails became completely solid, and his eyes lost its characteristics and became empty glowing circles, surrounded by a black mask of chakra.

In this form, the Nine-Tails had complete control over Naruto's body, making him a mere endoskeleton for its chakra. The chakra's internal support became Naruto's physical mass, with every living thing in its way a target. The four-tailed form had all the benefits of its previous tailed forms, but with upgrades. With a simple wave of his hand, it could create a shockwave of destruction. With the demon fox shroud being solid, its defences had reached to the extent that Orochimaru's legendary Sword of Kusanagi couldn't pierce through it, and could instantly burn another's skin on contact like as it were poison; depending how long and how much that person had touched it, it could take a lot of time and energy to heal the wound with just ordinary medical ninjustu. If Naruto was hit, the chakra itself could form another body and strike back almost instantly. Finally, Naruto had the ability to charge a Tailed Beast Ball, consume it, and then fire it in the form of a massive chakra blast with such force that it could destroy three Rashōmon gates. In the anime, it could generate numerous bodies, almost completely altering its own form into an amorphous blob, with which it was able to attack from all directions, and create a twister with just one slash from its claw.

In the end, the four-tailed form was Naruto's greatest downfall. Because the Nine-Tails' chakra was constantly destroying and creating new cells, it shortens Naruto's life, similar to Tsunade's Creation Rebirth. When the four-tailed form was finally repressed, Naruto needed immediate healing, as his skin was completely burned away. Naruto first slipped into this form when he was training with Jiraiya, who had used the key on the abdomen of the scroll toad, Gerotora, to weaken the Nine-Tails' seal for just a short time. And for that, it allowed enough of the Nine-Tails' chakra to leak out of the seal and produce the form, in turn almost killing Jiraiya.

Six-Tailed Form
During Pain's invasion of Konohagakure, and after Naruto's failed attempt to defeat the Deva Path, Naruto was left pinned to the ground when Hinata Hyūga challenged Pain in a desperate attempt to protect Naruto. Outmatched, Hinata was quickly dispatched, stabbed, and severely wounded by Pain's Chakra Disruption Blades. Infuriated, and believing Hinata to be dead, Naruto lost control of himself, and exploded into his four-tailed form, which quickly slipped into a six-tailed form, skipping the fifth tail altogether.

In this form, the Nine-Tails' bones begin to form out of the intense chakra around his body, attached to the body with several thick chakra ligaments. With its raw power, the six-tailed form was able to withstand Pain's Shinra Tensei and then reflect the attack back upon Pain himself. This form's demon fox shroud was so durable, even Pain's Chakra Disruption Blades couldn't penetrate it. Unlike the four-tailed form, the six-tailed form was able to unleash its Tailed Beast Ball without ingesting it first, and it had enough energy to create an enormous crater next to an already destroyed Konoha, even without being fully charged. In the anime, it could also rapid-fire smaller scale chakra blasts. Curiously, in the anime, the six-tailed form's demon fox shroud managed to swim through and direct a body of water with its own movement without vaporizing it, and also touched the Deva Path without burning him.

Eight-Tailed Form
As the Nine-Tails fought Pain through the six-tailed form, Naruto, within his subconscious, thought of Pain's plans for peace, and pleaded for someone to help him with a response. Through his suffering, the Nine-Tails tempted Naruto to entrust his heart to it so that it could destroy everything that was causing Naruto pain, thus distorting the seal and allowing the seventh and eighth tails to grow.

The eight-tailed form is his largest so far, being about the same size as the Nine-Tails, with muscle tissue beginning to grow on the bones from the six-tailed form. The only things missing in the eight-tailed form from the Nine-Tails are the ninth tail, skin, and fur. This form is so powerful, that it was capable of breaking through Pain's Chibaku Tensei with brute force. In the anime, for the brief time it was unleashed, it breathed a large stream of fire, which burned through the debris of the Chibaku Tensei, making it look like a meteor shower falling down toward the earth.

Full Nine-Tails Form
Unlike some other jinchūriki, Naruto cannot fully transform into his tailed beast when using the full extent of the Nine-Tails' chakra. This is due to the hostility that still exists between Naruto and the Nine-Tails. When he attempted this transformation, he instead transforms into a miniature, comical version of the Nine-Tails. It was also shown that Naruto cannot maintain this form for very long, as it drains him of the Nine-Tails' chakra significantly.

Nine-Tails Chakra Mode
After Naruto successfully separated the chakra from the Nine-Tails, and imprisoned the Nine-Tails itself with a new seal, he can access its chakra directly whenever he needs it without interacting with the Nine-Tails at all. In doing so, the chakra envelops Naruto, and the shroud takes on an appearance resembling the Sage of the Six Paths, with his new seal clearly visible. The colour of his eyes changes from blue to orange. Unlike the demon fox shroud, which is red and releases chakra as seething bubbles, this form's shroud is yellow and releases chakra as flickers of flame.

With the Nine-Tails' power under his control, Naruto's speed and strength are significantly increased. He can even use the shroud to create limbs, which can easily crush stone with just a grip. Naruto also gains the Nine-Tails' ability to sense negative emotions, something not even the best sensor-type ninja are capable of. Due to having the Nine-Tails' Yang chakra in this form, Yamato's Wood Release techniques reacted to the chakra's life-giving energy, turning his wooden totems into full grown trees within a matter of seconds. While trying to use the Rasengan in this form, it resembles how the Tailed Beast Ball is formed. However, using the Nine-Tails Chakra Mode is a very huge risk; Naruto has to temporarily "shelve" his own chakra in order to use the Nine-Tails' chakra, which allows the Nine-Tails to automatically drain his original chakra. If the Nine-Tails manages to take all of Naruto's chakra, he will die. Naruto is also restricted from using shadow clones, since the Nine-Tails would absorb every portion of Naruto's chakra for each shadow clone he makes, which would lead to instant death. Because of this, Naruto has to limit the amount of time he spends in this mode.

Trivia

 * Naruto's full Nine-Tails form resembles his true form in the Naruto Manga Pilot.