Kaguya Otsutsuki is a new, but the current main antagonist of the Naruto manga and anime series. She is a princess who became the first human ever to hold and use the power of chakra, which her twin sons inherrited from her.
Kaguya Otsutsuki was a princess from an unknown land that at least a thousand years before the series began decided it would be in humanity's best interests if someone were to eat the forbidden fruit of the Shinju, a god-like tree, doing so to gain the power to put an end to war and create world peace. Though she was successful at doing so with the god-like powers she gained and used her Infinite Tsukuyomi to create world peace, it only last for a limited time, possibly because of her mortality, and the people of the world began to fear her as a demon for her methods, despite them having been genuinely out of desire for peace. Kaguya gave birth to two children, Hamura and Hagoromo, who inherited her power of chakra, and she went on to try and gather all chakra for so she could split it evenly among her sons by creating the Ten-Tails, which was formed from both her and the Shinju. However it, and by extension she, was sealed within Hagoromo by him and his brother and later sealed away in the moon along with the Ten-Tails body by him later in life. Neither of her two sons ever seemed to know it was her. Its also been implied they may have gone against her at some point too. After she was sealed in the moon, Kaguya's will produced an artificial being later known as Black Zetsu, which considered her its mother, and it went on to influence history as it wanted in order to revive Kaguya.
After Madara Uchiha had nearly succeeded in completely trapping the world in the Infinite Tsukuyomi, Kaguya Otsutsuki's will finally enticed Black Zetsu to betray the mighty Uchiha elder and revive her in his immortal body by having him absorb all the chakra from the genjutsu's victims and fully merge with him, thus transforming Madara into Kaguya herself. Effortlessly overpowering Naruto Uzumaki and Sasuke Uchiha, Kaguya recognizes them as the the ones her grandsons' chakras had been reborn into and, telling Kakashi Hatake that she didn't want further harm to come to the earth since its her precious nursery, Kaguya teleports herself and her opponents to a different dimension and lets them fall towards a stream of lava, declaring she would wipe them out. Though they all avoid the lava, she, declaring all chakra to be hers and that it would become as one again, disabled Sasuke's hawk summon and proceeded to attack and easily overwhelm Naruto, before being attacked from above by Sasuke using his perfect form of Susanoo. Easily overwhelming him and destroying his Susanoo instantly, Kaguya teleported through a space-time rift and held Naruto and Sasuke by their chins, paralyzing them, and began crying as she saw the images of her two sons in them. As the fight continued, Kaguya was struck by Naruto after witnessing one of his perverted techniques, but proceeded to teleport everyone again into a different, icy dimension, freezing Naruto and Sasuke in ice before they could seal her. Moving away through a space time rift, Kaguya reached through another, grabbed Sasuke, and tossed him into a desert dimension at Black Zetsu's request, so she could fight and defeat one at a time and ruin their chances of sealing her.Continuously overwhelming Naruto as the fight continues, Kaguya summons them all to a gravity-heavy deminsion after Obito uchiha and Sakura Haruno manage to retrieve Sasuke, which ways down everyone, including her, Kaguya attempts to kill Naruto and Sasuke with her destructive bones, which miss. Adjusting, but allowing Kakashi Hatake and Obito to move again, Kaguya attempts to kill them again, only for Obito to take the hit and save the others. After Obito crumbles away, Kaguya has her left arm knocked off by Naruto, before proceeding to be overpowered by him and then once again overwhelming and destroyed Sasuke's perfect form of Susano'o. However, the Tailed Beasts within her then force a transformation on kaguya against her will, which emerges from the hole where her left arm was. Though she managed to subdue it, Kaguya went on to be sealed by the combined efforts of Team Seven, thus ended her threat and removing her essence and the Tailed Beasts from Madara's body
Kaguya was a very frightening person, but despite it she was a well-meaning woman who desired to create world peace, just as her son Hagoromo did. Unlike him, however, Kaguya opted for a more forceful approach, creating the Inifinite Tsukuyomi genjutsu and using it on the world to force them to submit to her will by putting their minds in a dream world so that war wasn't possible. This method only caused others to fear her as a demon, and though she still wanted to create world peace permanently after her revvial, it seemed she them also wanted to rule the world since she tried to create an army from the Infinite Tsukuyomi's current victims. Shes was also ruthless, as she tried to sacrifice one of her own descendants to be able to permanently achieve her goals, and moved to destroy Team Seven without any hesitance after her revival, seeing them as a threat to her plans, despite the fact that Naruto Uzumaki and Sasuke Uchiha were following her son, Hagoromo's wishes. Uniquely, she seemed to love the earth and its natural state, and didn't want any further harm to come to it after her revival. Despite their different views, yet similar desire for world peace, its been implied that Kaguya's fraternal twin sons, Hagoromo and Hamura, might have gone against her at some point and that, put together with them leaving her after growing up and ultimately sealing her in the moon(though they were unaware of her at this point) has caused Kaguya to develope negative feelings for them. However, she still showed motherly qualities as Black Zetsu, a product of her will, has stated that Kaguya wanted to gather all chakra to herself in order so that she could split it among her children and benefit them in a way, therefore making it likely that what they did to her feels like an ultimate betrayal. Kaguya also began crying when she saw the images of Hagoromo and Hamura in Naruto and Sasuke, which suggested she, as their mother, still loved them.
Kaguya Otsutsuki was easily the most powerful character in the series, her might being regarded by even her own son, Hagoromo, who himself is a legendary figure revered as a god, as being superior to everyone's, including his own. She was able to effortlessly overpower both Sasuke Uchiha and Naruto Uzumaki after Hagormo had given them huge power boosts, and dominated her battle with them, easily overwhelming both at once and proving too much to be overcome in terms of sheer power. After she consumed the original, forbidden fruit of the Shinju, Kaguya gained such god-like powers that she was able to easily put an end to all the wars of her era and even created the mightest genjutsu of all, the Infinite Tsukuyomi, with which she managed to created world peace for a temporary time. The way the genjutsu works is by trapping the minds of its victims in a dream world where their own ideal world is granted to them for as long as the jutsu stays active. The chakra reserves of Kaguya were extremely massive, being greater than even the Ten-Tails, which was said to have nearly infinite chakra. After her revival, upon witnessing her firsthand, Sasuke noted her chakra levels were greater than his, Naruto's, and even Madara Uchiha's after he'd become the Ten-Tails jinchuriki, despite the fact that his already had been excessively massive beforehand. He even shockingly wondered how someone so powerful as Kaguya could even exist. According to Black Zetsu, Kaguya, rather than the Ten-Tails, is the true progenitor of chakra itself. The fact that she was revived in Madara's immortal body likely made Kaguya herself fully immortal, as well as likely having all of his powers as well as the benefit of her own, putting her overall might and prowess at virtually invincible levels. She can extend her hair to use it as a weapon or possibly
absorb someone's chakra, as well as fire off a barrage of needles from it. She is able to effortlessly teleport herself and those around her to different dimensions instantly and on a whim, shown when she warped Team Seven to lava and ice areas before they could react, nearly killing them in the process.. Kaguya can produce chakra fists stronger than Naruto's Tailed Beast chakra arms, which it bests easily, and she also managed to easily destroy and overwhelm the perfect form of Susanoo Sasuke used and destroy it with ease, possibly in the same way. In her dimensions, Kaguya was able to merge with the area and manipulate nature at will to overwhelm an unknowing enemy. She has access to all of the Three Great Dojutsu; the Sharingan, the Rinnegan, and the Byakugan, with the first two taking a unison form in the third eye on her forehead. With this third eye Kaguya can cast the Infinite Tsukuyomi she had created, with her Rinnegan and Sharingan likely granting her access to all the fundemental powers of those dojutsu as well. With her Byakugan, Kaguya can see almost 360 degrees with telescopic, long-ranged, X-ray vision, having only a single blind spot at the first thoracic vertebrae. She is also able to open and move through space-time rifts to get around and take others by surprise easily. Like Madara Uchiha, as the Shinju's host, she is also able to fly and hover in the air. In one depiction of her, Kaguya also showed the ability to manipulate weather. She also has the Shikotsumyaku kekkei genkai of the Kaguya Clan, which she is more dangerous at using than te only other known user, Kimimaro, able to fire off bones spike that cause a target to reduce to ash if peirced.