The first was Zetsu, a member of Akatsuki, codenamed "Mystery."
Zetsu consisted of two halves: the right half was "Black Zetsu," while the left half was "White Zetsu." Though Black and White Zetsu were one entity, their personalities were entirely different. Black Zetsu was gloomy and sinister, while White Zetsu was comparatively easygoing.
White Zetsu possessed the ability to copy chakra. Through physical contact, he could replicate identical chakra and techniques, and sensory-type ninja could not detect him. During the Fourth Shinobi World War, White Zetsu served as Tobi's main fighting force, numbering over a hundred thousand. White Zetsu was a "shoddy product" cultivated by Uchiha Madara using the First Hashirama's cells. (In truth, they were living weapons created by Kaguya to deal with the Otsutsuki trio—Momoshiki, Urashiki, and Kinshiki—through Infinite Tsukuyomi and God: Deep Forest Emergence.) They were created using the Demonic Statue of the Outer Path as a medium. Since they were born from God: Deep Forest Emergence, they could turn into trees after death and were therefore classified among Wood Release users.
Black Zetsu, meanwhile, was actually the embodiment of the will of Kaguya Otsutsuki, the mother of the Sage of Six Paths—Kaguya's third son, in other words—and possessed seven chakra natures.
The second was Obito Uchiha, an Uchiha clansman and member of Akatsuki. Under the name Tobi, he had replaced the deceased former member "Scorpion." He had once been a ninja of Konoha and a member of Team Minato alongside Kakashi and Rin Nohara. During the Battle of Kannabi Bridge, he had been crushed by rocks while saving Kakashi and left on the verge of death. He entrusted his Sharingan, along with his wish to protect the girl he secretly loved, Rin Nohara, to his best friend Kakashi. Once believed dead, he was later rescued by