The Four-Tails (四尾, Yonbi)
is a tailed beast sealed within Roushi of Iwagakure
. It was captured by Kisame Hoshigaki, then extracted and sealed by Akatsuki. It was later resealed into a resurrected Roushi during the Fourth Shinobi World War. At a certain point in history, the Yonbi fell into the possession of Iwagakure and was sealed into Roushi for over forty years, who later left Iwagakure in a journey to gain a better understanding and control of the tailed beast. The Four-Tails has yellow irides, white pupils, red fur and green skin
. He primarily resembles a monkey, but has the build of a gorilla
. It also has horns on its forehead
, similar to the Third Tsuchikage's yellow jacket, as well as elongated canine teeth and spike-like protrusions on the four of its tails
. Its long canines appear to be broken and are darker at the end. In its mouth it has a big, round opening, from where it spits lava
, and it doesn't seem to have a tongue. The fur on its chin and on the top of its back resemble Roushi's beard and hairstyle. The Yonbi is a very prideful tailed beast, as it detests being called by the name "Four-Tails" and boasts about its lineage
. It uses 'ore' (オレ) when referring to itself. It also hates humans
, which from the fact that humans have enslaved it, and believing that apes are more intelligent than humans. However, when talking about the Sage of the Six Paths, it showed him great respect. Its real name is Son Goku (孫悟空, Son Goku)
- Yonbi has an enormous supply of chakra compared to most ninja. However, it does not have as much as the Nine-Tailed Demon Fox, gaining +400 chakra
- Complete mastery over the Lava element, without the use of handseals in the human and tailed beast forms and a +30 to Lava and Fire or Earth up to S rank.
- Ape-like abilities, compared to most of the other Tailed Beasts, Son Goku is better in hand-to-hand combat as a result of his ape-like body, which allows him to be preform technical maneuvers.
- Only Roushi bios can have the Four-Tails.
- Only one person can have a Roushi bio at any time.
- You need to have mastered the Fire and Earth elements