The Nine Tailed Beasts and Jinjuriki
Biology
Tailed Beasts are Immortal beings of Pure Chakra created around 1000 thousand years by the Sage of Six Paths Hagoromo Otsutsuki after Splitting the Chakra of 10 Tails and sealing his Mother Kaguya Otsutsuki. The Tailed Beasts have been sought out because their power and sealed inside humans that would be called Jinchuuriki given the human in question a variety abilities and large reserves of chakra. Though Tailed Beasts can die if the Jinnchuuriki host dies this is only temporary death and the beast will revive later on over time somewhere else. This in turn makes the Tailed Beasts practically immortal. Tailed Beasts also a great healing factor and if are badly damaged will progressively heal over time. Tailed Beasts are also genderless.