
nanami no kabutomushi (7 tailed horned beetle)
Background
According to Madara Uchiha, the Seven-Tails came into being in the waning days of the Sage of the Six Paths' life; to prevent its resurgence, the Sage split up the chakra of the Ten-Tailed Beast into nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. The Seven-Tailed Horned Beetle eventually fell into the possession of Takigakure and was sealed into Fū, but was captured and extracted by Akatsuki.