Nine Tails (Kyuubi),
Kyuubi no Youko

Tale in the Legend of the Tailed Beasts This is a bijuu in the shape of a nine-tailed fox, and the strongest of them all. The reason he is so powerful is simple: Kyuubi has an unlimited amount of power, earning it the King of Bijuu title. The power is generated by Kyuubis Fire Seal, and as a result, after battling for 100 years with Yamata no Orochi, it becomes exhausted; but Kyuubi continues standing, able to fight. It is also pretty cunning and smart.
Situation in the Ancient War of the 9 Gods Battled 4 times; All of them victories
Wins Nekomata, Houkou, Raijuu, Yamata no Orochi
Fate In unclear whereabouts, Kyuubi continues to kill all the people on his way to find the one who awakened him, and the one who managed to seal him before. (That being Yondaime, probably) Yamata no Orochi didnt tell Kyuubi, though, that the one who awakened him was the Eight Tails himself.
Japanese Myth Appearance: Kyuubi no Youko is the strongest (S Level) Bijuu of the Japanese Myth. Its body has a red fur; Kyuubi represents the element of Fire. Its abilities are incredible. Because it has never been defeated by any youkai, its total strength is unable to estimate. His tails create cyclones by spinning quickly, and Kyuubi proceeds to rip its enemies with its huge claws. At the same time his fur may shoot fireballs similar to meteorites endlessly, instantly destroying villages. In the ancient Bijuu wars, a challenge results in Houkou being severely wounded, and Nekomata nearly dying, but ending up being rescued by his master, Shinigami (God of Death). Yamata no Orochi depended on the Kusanagi no Tsurugi to fight Kyuubi, but was defeated and the sword received a cracked hole, courtesy of our kitsune.
Ability: Fire element attacks, Flaming claws, and other things depicted above
Bijuu Strength Ranking 1st
Bijuu Chakra/Stamina Ranking 1st
Symbolic Element Fire (God of Fire)
Origin / Discovered in Hidden Altar of Gods in Kobe