Saiken(Oozey)

Saiken (犀犬, Saiken), more commonly known as the Six-Tails (六尾, Rokubi), is a tailed beast sealed within Utakata of Kirigakure. It has been captured by Nagato in the anime, then extracted and sealed by Akatsuki. It was later resealed into a reincarnated Utakata during the Fourth Shinobi World War.

Personality
Though much has not been seen of Saiken's personality, the giant slug uses when referring to itself, 'ore' being a boastful way of saying 'I'. It also speaks with a dialect which may possibly be Ōsakaben.

Appearance
Saiken resembles a large, white, bipedal slug with stubby arms and feet. It has two prominent optical tentacles (eyes) and hole-like openings as a mouth. Its entire body is covered in a slimy substance. During the last remaining days of the Sage of the Six Paths, Saiken was much smaller but still larger than most humans.

Abilities
As a tailed beast, Saiken has a great amount of chakra and it is able to use it to create a Tailed Beast Ball. Saiken is able to emit corrosive, alkali substances that are extremely dangerous on contact in the form of a liquid or a gas, which was able to burn the skin of another tailed beast, such as Gyūki. The gaseous form was able to instantly disintegrate a tree that came into contact with it.

Trivia

 * literally means 'rhinoceros dog', apparently a kind of Chinese yōkai.