Hiruko (missing-nin)

is the main antagonist of Naruto Shippūden 3: Inheritors of the Will of Fire. He is a missing-nin of Konohagakure who wishes to plunge the world into a Fourth Great Shinobi World War, and then conquer it.

Appearance
Hiruko is a white-haired boy with red eyes dressed in an over-sized, high-collared coat wrapped with three leather straps. Most of his body is covered in bandages, including his mouth and arms, revealing only the upper half of his face and hair. By taking some of his bandages off he can use them to attack. Despite his youthful appearance, he is actually closer in age to the Sannin. Without his coat on, his hair extends past his shoulders and down to his hips.

Abilities
Though he was born with no natural special abilities, Hiruko compensates by using the Chimera Technique, a kinjutsu which he developed, allowing him to obtain Kekkei Genkai by integrating the bodies of other ninja with his own. Having already stolen four Kekkei Genkai from the other Great Nations, Hiruko possesses other abilities and physical traits from his victims, such as enhanced strength, and seeks to obtain more.

In addition to these abilities, Hiruko and his followers are able to use the Chimera Technique to produce creatures that are literal chimeras, including a large, bird-like monster that molts explosive feathers and wolf-like beasts that attack using appendages resembling tentacles.

Through his Chimera Technique, Hiruko has acquired four Kekkei Genkai: Steel Release, Swift Release, Dark Release, and Storm Release.

He also has a section on the palm of his hand where he can literally "absorb" the technique being thrown at him (in a manner not too different from Pain's Preta Path). He can also use the bandages wrapped around him as tendrils, strong enough to slice or smash through rocks.

Background
A contemporary and former friend of the Sannin, Hiruko wished to become a strong shinobi, yet was born with no natural special abilities. To overcome this disadvantage he developed the Chimera Technique, a kinjutsu which would allow him to obtain the Kekkei Genkai of other ninja by fusing their bodies with his own. Some time after the Third Great Shinobi World War, Hiruko divulged his findings on the technique and left the village as a missing-nin.

Dozens of years later, ninja possessing Kekkei Genkai begin disappearing from Kumogakure, Iwagakure, Kirigakure, and Sunagakure, leaving Konohagakure as the suspect and prompting rumors that they are preparing to rebel against the Land of Fire. When Konoha ANBU are dispatched to investigate, they encounter Hiruko and his followers, Ichi, Ni, and San. Hiruko reassures his followers that there's nothing to worry about, then quickly dispatches the ANBU squad with his Chimera Technique, absorbing their Earth-nature chakra and using it manipulate the mountain itself, crushing them.

With the other nations amassing troops on the borders of the Land of Fire and threatening to invade, Hiruko uses a genjutsu to project his image in the skies over Konoha and deliver a message, announcing that he intends to obtain the Kekkei Genkai of the Land of Fire, becoming immortal, and virtually invincible. With the combined power of Kekkei Genkai from all Five Great Nations, he plans to instigate a Fourth Great Shinobi World War and rule the world. With the plan in getting all of the Kekkei Genkai Hiruko eventually becomes interested in Kakashi's Sharingan. To get what he wants, Hiruko goes as far as controlling him. In order to carry out the rest of his goals, Hiruko has been biding time so that he can draw power from the Sun's corona during a solar eclipse.

While he did succeed in assimilating Kakashi while he was under his control, the seal that Tsunade used on him activated Kakashi's Mangekyou Sharingan for the purpose of blasting him to another dimension via Kamui (which would cost Kakashi's life as well). Naruto was able to block this via extracting Kakashi out of his body. Nonetheless, he was still able to put the Konoha 11 in a collective pinch by summoning the chimera body of his subordinates. A delaying tactic was employed by Kakashi and Naruto using multiple Great Ball Rasengan and Raikiri before the latter ultimately took him down with a large Rasen Shuriken, effectively disintegrating his youthful body. As he reverted to an old man, Kakashi joined him in reflecting about the futility of finding perfection in solitude and the importance of connecting with comrades before passing away.

Trivia

 * translates roughly to, "a call to halt vulgarity".
 * Hiruko is also the deformed child, in Japanese Shinto mythology, of Izanami and Izanagi.
 * Hiruko (蛭子) can be translated to "leech child", a possible connection to the Chimera Jutsu's ability to "leech" the bloodline and nature affinity from his enemies, as well as his youthful appearance despite his age.
 * Hiruko has the highest number of Kekkei Genkai in the entire series currently (although not his originally).
 * Storm Release, Swift Release, Steel Release and Dark Release each originates from the other four Great Ninja Countries, except the Land of Fire.