8 tailed bijuu

八尾 | 八岐大蛇 -
Eight Tails (Hachibi),
Yamata no Orochi
Yamata no Orochi is a Snake bijuu. It has crimsom red eyes, eight heads and eight tails (also depicted to having trees and vines growing around them) and has the power of the Demon world, a symbol of evil. Each head of Yamata no Orochi represents a symbol: Soul, Ghost, Evil, Devil, Monstrous, Kill, The Afterworld and Death.
Its powers were originally weak, the members of the Kusanagi clan, when attacking it, acted carelessly, using the legendary sword Kusanagi no Tsurugi (Oro’s sword). Because of that, as a consequence, Yamata no Orochi takes the sword from them, absorbing the power contained inside, and becoming an incredibly powerful creature, and finally storing it in its body.
With the new power, Yamata no Orochi releases an insane amount of dark energy, awakening the other Bijuu and becoming arrogant. Yamata no Orochi proceeds to defeat many of the Bijuu, but when it battles with Kyuubi, it is defeated. The cause of this is simple: Kyuubi has an unlimited amount of power, making even a hole in the Kusanagi sword. As this happens, it shows how tremendously powerful Kyuubi is, deserving of the “King of Bijuu” title. Not even Sarutobi and Enma (I’m not sure how those two are into the legend) could scratch the Kusanagi no Tsurugi. (That makes connections to the Oro x Sandaime battle)
Legend also depicted it as having a power able to rival Kyuubi’s [in quality], but the fact is, Yamata no Orochi’s does have a limit.