Black Zetsu

was the physical manifestation of Princess Kaguya Ōtsutsuki's will. It secretly instigated many of the events that shaped the shinobi world to secure Kaguya's revival. To further its plans, it partnered with White Zetsu to become half of the Akatsuki member known simply as.

Background
Black Zetsu was created by Kaguya Ōtsutsuki shortly before she was sealed as the Ten-Tails by her twin sons, Hagoromo and Hamura. When Hagoromo later named his younger son, Asura, as the new leader of Ninshū, Black Zetsu tempted Hagoromo's elder son, Indra, to go in war with his younger brother. It decided that Indra's descendants: the Uchiha, would be the main cast of the shinobi history it was creating and also modified Hagoromo's tablet to claim that among other things; the Infinite Tsukuyomi would be the Uchiha's salvation. Over the centuries, it manipulated the two brothers' reincarnations in an attempt to get one to awaken the Rinnegan, and also recorded many events for Kaguya, including Madara Uchiha and Hashirama Senju's last fight at the Valley of the End.

When Madara had seemingly created White Zetsu and its clone siblings, it was actually Black Zetsu pulling the transformed humans from Kaguya's Infinite Tsukuyomi out of the Demonic Statue of the Outer Path. When Madara was on the verge of death, he believed he had created Black Zetsu by imbuing his will into half of White Zetsu, and that the complete Zetsu was partially his clone. Zetsu later accompanied Obito Uchiha to Amegakure to locate Nagato, who had unknowingly been given Madara's Rinnegan as a child, and watched as Obito introduced himself as Madara Uchiha.

Personality
Compared to White Zetsu, Black Zetsu, nicknamed, is more serious and knowledgeable. In the Japanese version of the manga, Black Zetsu only uses katakana for okurigana and furigana. This is often conveyed in the anime through a deeper voice. After being reunited with Kaguya, it spoke with a softer, more human voice. While it and White Zetsu sometimes had differing opinions, the two halves were still able to function as a single entity.

Black Zetsu had the skill of appearing extremely trustworthy, obedient and loyal, being entrusted with Akatsuki's secrets and knowledge of Madara's Eye of the Moon Plan. In actuality, however, its true loyalties were kept secret from nearly everyone, including Madara himself. Unlike White Zetsu, who was kind to his allies, Black Zetsu expresses a belief that anyone beneath Madara is useless. When Obito lost the tailed beasts, Black Zetsu commented on how it was a more effective servant to Madara. It also had no qualms about using Obito's dying body as a host when it fought Kakashi Hatake and Minato Namikaze, showing how little it cared about the Uchiha's welfare, while deriding Obito for being useless for his treason. However, Black Zetsu's loyalties do not truly extend to Madara either, having feigned being created by the man in order to manipulate him discreetly which occurred for many years, and then harshly betrayed him and expressed to him how he was really no different from Obito. Black Zetsu even refers to Hagoromo's ideals of ninshū as absurd and his original text on the stone tablet as garbage.

Zetsu's main role within Akatsuki was to function as a spy, with other duties that were similar to those of a hunter-nin. It was able to control its body and take part in the tailed beast sealing ritual simultaneously, which, in addition to being unique to it, allowed it to act as a lookout while the sealing took place. When an agent of Akatsuki, or possibly even a member, died, Zetsu was sent to devour their bodies so as to not have their secrets revealed, further adding to its nature as a half-plant creature. Zetsu was also the one sent to retrieve the rings of dead Akatsuki members. Due to the role it played, Zetsu was the only member of Akatsuki to act without a partner on a regular basis. It operated on its own, often moving between the different locations where the other Akatsuki members were located. This resulted in other members reporting directly to it, rather than the figurehead leader, Pain. Zetsu would in turn report directly to Pain as well as Obito, the organisation's benefactor and eventual leader.

Black Zetsu is generally harsh and critical of nearly everyone it comes across, with the exception of its creator, Kaguya. Referring to itself as her son, it shows a deep reverence and devotion to her and is willing to go to any lengths to please her. It even goes as far as to encourage others to sympathise with her predicament following her sealing. Black Zetsu's determination to aid the one it calls mother runs so deep that it spent countless years influencing the shinobi world in order to facilitate her revival, even claiming that the history of shinobi exists only to bring her back. Believing itself to be the progenitor of the shinobi history, Black Zetsu thinks very highly of itself, and grew angry at Naruto for even daring to touch it, believing him to be unworthy to do so. Interestingly, when it first referred to itself as Kaguya's child, Black Zetsu's tone and demeanour was noted by Sasuke Uchiha to have changed. It appears in the end, Black Zetsu's true loyalties reach only to Kaguya Ōtsutsuki, a person it claims to be the will of, and whom it affectionately refers to as ; Naruto even goes so far as to call Black Zetsu desperate to be at Kaguya's side, likening it to a snot-nosed brat who never wanted to leave its mother's side, and thus unable to realise that while it may have influenced shinobi history, said history was in fact built upon by the lives and deaths by many ninja.

Appearance
Black Zetsu's true form is a completely black, humanoid figure lacking any hair or visible orifices, made up of a black mass which it can shape and resize at will. The black mass contains two yellow eyes, which lack any visible sclerae or pupils, and it occasionally shapes itself to form a mouth with jagged teeth. Black Zetsu appears to have only retained one eye after being placed within White Zetsu by Madara, though it regained the second eye upon Kaguya's revival. Black Zetsu's eyes and consciousness can move to any point of the black mass, even if it is split into multiple parts. It is able to cover the body of another living being and control it, and its eyes can vanish entirely if it is possessing a body with a dōjutsu it wishes to make use of.

After it merged with the deformed right half of White Zetsu, the two Zetsu were easily distinguished by the Venus flytrap-like extensions that emerged from their sides, enveloping their head and upper body as a shell, which they were able to open and close. Beneath these extensions, Black Zetsu had short green hair, originally coming from White Zetsu. Under their Akatsuki cloak, they wore blue pants and sandals, and had both legs wrapped in bandages, which hid the area where the black mass on their right leg merged with White Zetsu's white foot. White, screw-like dots protruded out along the edges and collar of Black Zetsu. Black Zetsu wore the duo's green Akatsuki ring, which bore the kanji for, on its right little finger. In the anime, Zetsu's fingernails were painted pink and their toenails, as seen in their début, were blue.

When the two halves split apart, their plant-like extensions would separate and hang from the waists of both. Any clothing they were wearing, including their Akatsuki mantle, would split along with them, usually causing them to discard their torn clothing. When either of the halves emerged from the ground while split, their plant-like extensions would surround them in a circular formation. The two also demonstrated the ability to grow an additional leg from their white body mass to substitute for their missing half when split.

In the anime, Black Zetsu was seen wearing a purple robe with light sleeves and a straw hat reaching down to his ankles.

Abilities
Fitting its parasitic nature, Black Zetsu has shown many abilities that ultimately aided it in deceiving and manipulating others for centuries, all while remaining hidden and anonymous. With the powers at its disposal and tactical capabilities in combination with Kaguya's, the two were able to easily fend off both Naruto Uzumaki and Sasuke Uchiha, despite the two being aided by their respective enhancements and help from their allies. It could also use all five basic nature transformations and Yin and Yang Release.

Unique Body
Unlike a normal body, its could survive being bisected, and not age for over a thousand years. Being a product of Kaguya's will, Black Zetsu itself is also able to manifest its will to gain influence over others, either by subtly manipulating their thoughts or forcefully manipulating their bodies by attaching himself to them. He was able to render Madara, as the Ten-Tails' jinchūriki, completely powerless to resist his influence by impaling him through the chest with Obito's left hand. Black Zetsu, over time, has used this ability to stay hidden while manipulating many of Asura and Indra's reincarnations, including Indra himself. Fitting its malleable physiology, Black Zetsu has shown the ability to alter its form and shape, being able to form itself into a humanoid shape or stretch to great lengths. Used throughout the centuries, Black Zetsu is able record the events it observes, as well as show these "recordings" to others by merging with them.

By attaching itself to others, Black Zetsu is able to control the target's body and use their abilities, kekkei genkai or kekkei mōra as its own if they are in a weakened state. Black Zetsu melding with someone also has the effect of sustaining their life, allowing them to temporarily survive such things as using a sacrificial technique or having a tailed beast extracted from them. However, should the target regain control of their body, they can prevent Black Zetsu from detaching itself, thus using this trait against it.

Ninjutsu
Being a sensor, it could sense individuals, many kilometres away, and distinguish between distinct chakra signatures, being able to locate Asura and Indra's reincarnations. While attached to Kaguya's arm, it could produce bones which turn their targets to ash, as well as open portals to fire these bones through. In its original form, it has shown the ability to phase and travel through its surroundings. Black Zetsu is also able to absorb and distribute chakra through physical contact. In the anime, keeping with its sneaky nature, Black Zetsu could conceal itself by blending in with the environment. It was also able to manipulate a giant boar through unknown means and seemingly strengthen it, as noticed by Asura Ōtsutsuki when the boar not acting normal.

Wood Release
While possessing White Zetsu's body mass, Black Zetsu had access to Hashirama Senju's cellular material, allowing it to utilise Hashirama's Wood Release, albeit on a much weaker scale. Black Zetsu accomplished this by transforming its white body mass and plant-like extensions into roots during battle. It has been seen to have a high amount of proficiency with Wood Release, holding its own against Mei Terumī, a clone of Naruto Uzumaki, Chōjūrō, and the rest of the Daimyō Protection Squad with it.

While Black Zetsu was attached to White Zetsu, their signature technique was Mayfly, which allowed them to merge with the ground to quickly travel to a new location, though not as quickly as Obito's space–time travelling. This technique was ideal for Zetsu's function as a spy, as it erased their presence and prevented them from being sensed. In addition to functioning as a single entity by communicating through their thoughts, Zetsu's two halves were able to split apart, allowing them to act independently. While separated, the two halves could extend roots underground to communicate with each other over long distances.

Rinnegan
In an attempt to ensure Madara's revival via the Outer Path — Samsara of Heavenly Life Technique, Black Zetsu took possession of Obito, forcing him to use the technique specifically for the purpose. In a later attempt to aid Madara in retrieving his left eye from Obito, Black Zetsu was able to steal possession of the latter's Rinnegan while almost completely removing itself from Obito's body.

Sharingan
When Black Zetsu was finally able to return the Rinnegan back to Madara, he received Obito's original left eye in exchange. Wielding both of Obito's Mangekyō Sharingan, Black Zetsu was able to utilise the left eye's Kamui to travel to and from an alternate dimension while bringing another person with it. Upon detaching itself from Obito, Black Zetsu no longer has access to the former's Mangekyō Sharingan.

Intelligence
Influencing and manipulating many prominent and deceptive individuals throughout history including Indra, Madara Uchiha, Obito Uchiha, Nagato, Kabuto Yakushi, and a countless amount of others, Black Zetsu proved itself to be a highly deceptive and cunning individual. In order to further its plan to revive its creator, Kaguya, Black Zetsu has influenced many events to secretly manipulate those most useful to it. With the goal of manifesting a Rinnegan in one of its pawns, Black Zetsu even orchestrated the Uchiha and Senju clan's extensive rivalry. In order to set the Eye of the Moon Plan in motion, Black Zetsu rewrote Hagoromo's Stone tablet so that Madara would find it and become an unknowing pawn. To further gain Madara's trust, Black Zetsu also tricked him into thinking that it was an extension of the former's will, feigning undying loyalty. Additionally, orchestrating Akatsuki's goal to capture the tailed beasts and Kabuto's alliance with Obito, Black Zetsu claimed that the entire Fourth Shinobi World War went all according to its design. In fact, it believes that because it had such a substantial influence over the events that have taken place throughout the history of shinobi, all of it is essentially his tale of reviving Kaguya. Having lived for centuries due to the fact that it was created at the beginning of time, Black Zetsu has amassed more information about the shinobi world than almost any other individual.

In battle and alongside its creator, Kaguya, Black Zetsu has shown to be an adept tactician who can analyse its opponents and suggest appropriate countermeasures to their tactics, which Kaguya complies with and carries out. While attached to her severed arm, Black Zetsu was able to inventively use her All-Killing Ash Bones and its ability to create rifts in space, in unison, in an attempt to intercept Naruto and Sasuke's attempt to seal the former.

Other Skills
Despite having neither the Rinnegan nor the Sharingan, at the time, Black Zetsu was able to read and rewrite the text on the stone tablet. Should the need arise, Black Zetsu is capable of telepathically communicating with other individuals. Through unknown means, Black Zetsu was able to manipulate the Demonic Statue of the Outer Path and release the White Zetsu trapped within it. Additionally, Black Zetsu has proven strong enough to harm and impale Madara Uchiha, despite his durability and considerable regenerative powers being greatly enhanced as the Ten-Tails' jinchūriki.

Sasuke Recovery Mission
After Sasuke and Naruto's fight at the Valley of the End, Kakashi and Pakkun appear to bring Naruto back home. As the three begin the journey back home to Konoha, Zetsu appears from the ground, having witnessed the whole battle. Later his silhouette appeared with the rest of the Akatsuki members where they discussed Orochimaru taking Sasuke Uchiha, the capturing of the Nine-Tails and the furthering of their plans.

Kazekage Rescue Mission
During the extraction of the One-Tail, Zetsu is told by the Akatsuki Leader to use his real body to use as a lookout, in which he identifies several enemies such as Team Guy, Team Kakashi, as well as Chiyo who was with the latter. Later, he is sent to dispose the corpses of Mukade and Yūra, finding Mukade a delicious meal.

After Sasori and Deidara were defeated, Zetsu and Tobi were sent to retrieve their rings, and dispose of their corpses. However, he was unable to eat Sasori due to him being a puppet, but was amazed to finally see what the real Sasori looked like. Tobi found Sasori's ring, wishing to take his place. Black Zetsu thought this was a bad idea, but White Zetsu thought otherwise, noting that Tobi was a good person. They later found Deidara's severed right arm and believe him dead until he arrived and proved them wrong. This caused Black Zetsu to wonder why Deidara hadn't captured Naruto Uzumaki, to which Deidara replied that he had already fulfilled his quota either way.

Akatsuki Suppression Mission
After Hidan and Kakuzu defeated Yugito Nii, Zetsu appeared to retrieve Yugito, and asked if Hidan was finished with his long winded ritual. When Hidan claimed that they were infidels ignorant of prayers, Zetsu told him that when sad and alone, all one can count on is yourself. Kakuzu disagreed, stating that money was all one could count on. White Zetsu agreed that money was important, however Black Zetsu stated finding the next one was much more important. Zetsu is later seen sealing the Two-Tails.

Itachi Pursuit Mission
After Deidara's death, Zetsu was sent to recover his body, with White Zetsu wondering what happened to Tobi. Black Zetsu mentioned that based on the damaged area, he was most likely caught up in Deidara's explosion. Later, when Pain had encouraged the organisation to mourn Deidara's loss, White Zetsu took it on himself to mourn for Tobi's loss, while Black Zetsu thought such a notion was ridiculous.

Tale of Jiraiya the Gallant
After Pain's fight with Jiraiya, Zetsu revealed himself to have been watching the whole battle. As Pain announced he was going to capture the Nine-Tails, White Zetsu said it would be an interesting battle and wanted to go. However, Black Zetsu had another battle in mind, and they decided to watch Sasuke's battle with Itachi.

Fated Battle Between Brothers
Both halves spectated and commenting on the battle, with Black Zetsu offering knowledge on various Sharingan abilities. When Itachi died, Zetsu noted that Itachi shouldn't of been that weak, believing him to have already been afflicted prior to the battle. He later appeared near Tobi while he was engaged in combat with the Eight Man Squad, to report to him the result of the fight. They then led Tobi to where Itachi and Sasuke were, with Black Zetsu confirming to Tobi that he had indeed recorded the fight. After a meeting with Taka and Kisame, Tobi met with Zetsu on a bridge where they discussed the fact that Itachi — who had been hampering their plans — was dead and Zetsu lamented on the fact that so many Akatsuki members had died. Tobi said their deaths were worth it because Sasuke was in his hands now.

Six-Tails Unleashed
In the anime, Zetsu was present alongside the other Akatsuki members when they extracted the Six-Tails from Utakata.

Pain's Assault
Zetsu is present when Akatsuki begins sealing the Eight-Tails, and when it is revealed that the jinchūriki fooled Sasuke and replaced himself with a tentacle, White Zetsu flew into a hysterical laughter, which greatly annoyed Black Zetsu. Upon Nagato's death and Naruto returning to the village crowned as a hero, Zetsu revealed himself to have hidden inside a tree, watching the entire fight between them, hardly believing Pain to have been defeated, but decided to relay the information to Tobi. He then returns to Tobi and Kisame, reporting Nagato's death and betrayal, also mentioning that Konan wouldn't be returning either.

Five Kage Summit
Zetsu finds Tobi after the latter had encountered Taka, revealing that Konoha had already been destroyed, and that Danzō had been named the acting Hokage. He then mentioned to Sasuke that Naruto had defeated Pain, and was probably stronger than him. When Taka agreed to go to the Kage Summit, Zetsu split in half. White Zetsu proceeded to lead Sasuke and his team to the Kage Summit while Black Zetsu remained behind and discussed with Tobi the fact that they might lose control over Sasuke and would therefore lose their last chance to have someone sync with the Demonic Statue of the Outer Path. Tobi declared that he was tired of hiding, and explained that they needed to speed up the "Eye of the Moon Plan".

White Zetsu and Black Zetsu meet up at the site of Killer B and Kisame's battle only to reveal that Kisame's decapitated body was actually one of White Zetsu's shape-shifting clones. It is then revealed that Kisame, by having the clone fake his death, was then able to infiltrate Kumogakure while inside Samehada which was being carried back to Kumogakure by Killer B who intended to use it as his own weapon. Black Zetsu then stated that it was their feeding time and that they should merge once again.

Fourth Shinobi World War: Countdown
At some point, Black Zetsu reveals the corpse of Madara Uchiha to Kabuto, allowing him to resurrect the ancient Uchiha to use in the upcoming war. In the anime, Zetsu sees off Tobi before he made his journey to Amegakure to retrieve Nagato's Rinnegan. Upon Tobi's acquisition of the Rinnegan, Zetsu informed him that the scroll with the information that Kisame Hoshigaki sent through his messenger shark had arrived, also noting that everything seemed to be going in their favour. Zetsu later accompanies Tobi as he shows Kabuto around the Mountains' Graveyard, but questions if Tobi should really trust him.

Fourth Shinobi World War: Confrontation
Supervising Sasuke's recovery, Zetsu told him to be patient when asked if his bandages could be removed, remarking that when he did regain his sight it would be to a different world. As the Fourth Shinobi World War commenced, Black Zetsu separates from White Zetsu separate to carry out his assigned tasks. Before departing, Black Zetsu confirms to Tobi that White Zetsu's spores had been placed on Kabuto's body.

Emerging from the ground near the daimyō's hideout, Black Zetsu infiltrated the structure, despite alerting the enemy to his presence. However, upon discovering the daimyō's absence, Black Zetsu retreated and declared that they shouldn't underestimate his capabilities, as he was a part of the very land itself. Later locating his desired targets, he was instead obstructed by Mei Terumī and her squad, but sensing the Eight and Nine-Tails' chakra while confronting the team, he immediately communicated this to Tobi via White Zetsu. Told that the daimyō were no longer necessary with their quarry now in the open, Black Zetsu was ordered to continue with his guerilla tactics against the Mizukage's team to keep them from regrouping with the rest of their forces. The fight continued throughout the night.

Continuing to battle with Mei and her squad, Black Zetsu observed the arrival of Naruto's shadow clone to their location, who then proceeded to crash into a tree beside him. Growing roots from portions of his body whilst fighting, he used them to trip Naruto and avoid his Rasenshuriken, only to be bisected from behind by the enlarged blade of Chōjūrō's Hiramekarei. Immobilised, Black Zetsu wondered how the sword grew to such a size in an instant and was then sliced in half and pinned to the ground by Chōjūrō's blade as the Mizukage departed. Having been reincarnated, Madara telepathically communicates with Black Zetsu, ordering him to keep watch on Obito until after his "playing" with the Five Kage is done. Subsequently, Black Zetsu seeps into the ground, escaping.

Birth of the Ten-Tails' Jinchūriki
With Obito weakened after the tailed beasts were extracted from him, Madara enacted his trump card. With this, Black Zetsu suddenly emerged from underground and restrained him. As he began to meld with half of Obito's body, Madara was able to force Obito into using the Outer Path — Samsara of Heavenly Life Technique. Apologising as this all unfolded, Black Zetsu noted that from the start, this was his sole purpose for existing. With Madara's revival a success, Black Zetsu attempts to retrieve Madara's Rinnegan eye from Obito until Minato and Kakashi intervene. Black Zetsu once more melds with Obito's body, using the Uchiha's body to battle his former team and noting that his merger was the only thing keeping Obito alive. While both sides were at a stalemate, the Demonic Statue of the Outer Path emerged from Obito's artificial body, quickly being teleported. Afterwards, Black Zetsu again attempted to take the left Rinnegan. Obito, managing to resist Black Zetsu's control of his hand, told Kakashi to destroy the Rinnegan. Black Zetsu, realising what the summoning of the Demonic Statue meant, informed his enemies that Madara has regained his right Rinnegan.

Standing to face Minato and Kakashi in battle, Zetsu complained about the duo's stubbornness before Gaara arrived along with Sakura and a dying Naruto to their location. Black Zetsu managed to steal Kurama's Yin half when Minato tried to transfer it into his son, thus becoming its jinchūriki. Soon afterwards, Zetsu was joined by Madara who complained about having to come all the way there. As Black Zetsu attempted to return to Madara, bringing with him Yin-Kurama and Madara's missing eye, Obito overpowered him, keeping him merged to his body and he spoke with and subsequently attacked the legend. As Kakashi and now Obito were determined to save Naruto, the two use their respective Kamui to send Naruto to the other dimension and soon afterwards Obito as well. Once there, under watch of a sceptical Sakura, Obito proceeded to transfer Yin-Kurama into Naruto.

Later, after Madara managed to teleport himself using Obito's original Sharingan, which he took from Kakashi, he overpowered Obito and reclaimed his Rinnegan, allowing Black Zetsu to regain control of Obito's body. Madara also implanted Obito's original Sharingan back into his body in order for Black Zetsu to use its power. When Madara began casting the Infinite Tsukuyomi, Black Zetsu was unaffected.

Kaguya Ōtsutsuki Strikes
During the Infinite Tsukuyomi, Black Zetsu noted that the moonlight could not shine through Sasuke's Susanoo due to his Rinnegan. After the genjutsu ended, Madara managed to confront Team 7, but was stabbed from behind by Black Zetsu, who admonished a confused and shocked Madara for believing that he was any different than Obito and that he himself couldn't be used. After a distraught Madara stated that Black Zetsu was supposed to be his will, he declared that he is in reality "the will of Kaguya". Following this declaration, Black Zetsu proceeded to spread all over Madara's body as the latter screamed in anguish, whilst forcing the chakra of the people caught in the Infinite Tsukuyomi out from the ground and having Madara absorb it, turning him into a gargantuan blob. When it was completely covered by Black Zetsu, Madara's body shrunk and changed, bringing forth the revived Kaguya in his place.

Two incarnations of Black Zetsu once again re-emerge to absorb Naruto and Sasuke's chakra. While attached to their bodies, Black Zetsu shows and explains to them what he did to ensure Kaguya was revived. After he is completed, he attempts to return to Kaguya, but Naruto and Sasuke manage to regain control of their bodies and rip Black Zetsu off themselves, preventing him from absorbing any more chakra. He notes that Naruto and Sasuke are too rebellious, and that they can't do anything to Kaguya. Nonetheless the duo attack Kaguya and prove to be surprisingly effective in their coordinated strikes. It is then when Black Zetsu suggests to Kaguya that she separate the two in order to pick them off one by one. Kaguya complies with this by promptly sending Sasuke to another dimension.

As Kaguya goes to deal with Naruto, the crafty ninja begins drawing aid from the tailed beasts within him, ploughing through Kaguya's defensives and quickly overwhelming her with a massive army of shadow clones, calling it his own "personal dimension". The princess quickly retreats through her portal, to which Naruto quickly follows through, as does Obito along with Sakura and Naruto's clone. While the shadow clone quickly disperses, Black Zetsu is shocked that Naruto could follow them to the base world of Kaguya's various dimensions. While Kaguya is determined to "reclaim" the massive chakra within Naruto, Black Zetsu points out that Naruto is too dangerous and should just take the easier route of killing him. Dismayed in agreeing, Kaguya then launches a a jagged bone barrage on Naruto that impales him and starts to crumble. Kaguya then returns to the normal dimension, only to find that Naruto's shadow clone army didn't disperse. Black Zetsu realised that they were played, as the Naruto in the other dimension was also a clone. As Kaguya continued to destroy clones one at a time, Obito returned from Kaguya's dimension with Sasuke. Realising the threat of Sasuke and Naruto reunited posed, Kaguya shifted dimensions again to one of extreme gravity.

As Naruto and Sasuke were pinned from the natural force, Kakashi and Obito moved to shield the younger ninja from Kaguya's attack with their own body. Ultimately, only Obito was struck as he used Kamui to save Kakashi from his projectile. As Obito began to crumble away, Naruto desperately tried to save him with his Yang powers, to which Black Zetsu mocked his efforts as futile, noting further that Obito is a disgraced man who will never be forgiven for his actions. After Obito finally dispersed into dust, Black Zetsu openly expressed his relief in Obito's passing. Angered by this, Naruto quickly attacked, severing Kaguya's left arm and Black Zetsu with it. Naruto then used two of his Truth-Seeking Balls as rods to pin Black Zetsu down. As Naruto and Sasuke continued to pressure Kaguya, the Uzumaki bombarded Kaguya with nine separate attacks imbued with the each of the tailed beasts' powers, respectively. While surviving the assault, Kaguya's body began breaking down, morphing into an amalgamation of the tailed beasts, speculated by Black Zetsu to be caused by the will of the tailed beasts reacting to Naruto. Kaguya's body then began producing several massive hands that attacked in every direction. As one of them approached Sakura, Kakashi, having inherited Obito's chakra and Sharingan powers from the departed spirit, saves her with his newly awakened Susanoo, much to Black Zetsu's shock.

Despite Black Zetsu's fears for its creator, Kaguya ultimately regained control and formed the tailed beast-mass into a giant Truth-Seeking Ball. As Team 7 prepared for quite possibly their final mission, they launched a group attack that with well-coordinated efforts from their respective abilities landed a decisive group blow on the princess, greatly surprising Black Zetsu. Ultimately, Kaguya reverts back into the Demonic Statue of the Outer Path before ejecting Madara and the tailed beasts, and begins to be resealed within the moon. As Black Zetsu resolved to wait for another opportunity to revive Kaguya, Naruto arrived noting he had not forgotten about it. After a brief exchange Naruto hurled Zetsu into the satellite along with its creator, leaving Black Zetsu trapped in the satellite while also ironically granting Black Zetsu's long desired wish of always wanting to be at its "mother's" side.

Road to Ninja: Naruto the Movie
Zetsu was responsible for sending several clones disguised as deceased Akatsuki members to attack Konoha at the beginning of the movie. Later, he was seen with Tobi after Naruto and Sakura returned to their world, noting that they were so close to capturing the Nine-Tails.

Creation and Conception
In Naruto Hiden: Sha no Sho Character Official Data Book, Kishimoto revealed that he had originally planned for Akatsuki to be a group of monsters, "with almost no human characteristics", and that Zetsu's design was modelled after an insectivorous plant. He also stated that he had decided to make Zetsu half black and half white to "better show his split personality".

Trivia

 * The name means "tongue". A fitting name, as Black Zetsu was referred to as   based on his personality.
 * According to the databook:
 * Zetsu's hobby is observing unique shinobi.
 * Zetsu wishes to fight people who are likely to leave behind a corpse that will make a good meal.
 * Zetsu's favourite food is "chewy" people, while his least favourites are konnyaku and jelly.
 * Zetsu's favourite phrase is, which roughly means "The only one you can count on is yourself".
 * Wherever Tobi is, Zetsu is never far behind.
 * In the fourth databook, neither kekkei genkai nor kekkei mōra is listed among Zetsu's special characteristics, despite it possessing both through its host bodies at different times, and through Hashirama's cells. Similarly, none of the techniques that Zetsu used listed it as a user.
 * After escaping from Chōjūrō in its real shapeless form, Black Zetsu is then seen possessing another White Zetsu-like body mass when attacking Obito. This white mass completely disappears when Black Zetsu merges with Obito's body, but then is immediately restored when Black Zetsu leaves said body. The white mass finally disappears when Black Zetsu merges with Obito for the second time.
 * After Black Zetsu covered Obito's body, the Uchiha talks to Madara and slowly forms what appears to be a Truth-Seeking Ball over the back of his left hand, which then pierces through it to become a Khakkara. At the same time, Black Zetsu seems to vanish from the hand, suggesting that it was turned into the black orb.

Quotes

 * (To Hidan) White Zetsu: "When you're sad and alone…" Black Zetsu: "…The only one you can count on is yourself."
 * (To White Zetsu) "A weapon's strength or weakness is dependent on the user's ability to use it. An expert with a pebble can still beat a novice with a shuriken."
 * (To Minato and Kakashi) "I'm Madara's will. I'll eliminate whoever stands in his way. You and Obito took Madara way too lightly, and you underestimated me as well."
 * (To Madara) "You're not the saviour… and it's not over. Why do you think, that unlike Obito, you can use everyone else? Why would you be any different?", "That's not true either! My will is… Kaguya's!"
 * (To Naruto) "You… you're just another part of the shinobi history I created! A brat like you can't touch the likes of me—"