Is Zero-Tails a Tailed Beast in Naruto?

In Naruto, Tailed Beasts are regarded as the most powerful possessions in the Shinobi world. These magnificent creatures can wreak havoc if they fall into the wrong hands, which is why they are sealed to an individual who is potentially a strong Jinchuriki. Tailed Beasts can be mistaken for enormous mythical creatures, but in actuality, they’re the physical manifestation of Chakra itself.

There are basically nine Tailed Beasts that have been introduced in the series so far. They are One-Tails (Shukaku), Two-Tails (Matatabi), Three-Tails (Isobu), Four-Tails (Son Goku), Five-Tails (Kokuo), Six-Tails (Saiken), Seven-Tails (Chomei), Eight-Tails (Gyuki), Nine-Tails (Kurama) and lastly Ten-Tails.

Moreover, there is also a Zero-Tails, but its identity as a Tailed Beast is not one would expect.

---

What actually is the Zero-Tails in Naruto, explained

Zero Tails (Reibi) was never a Tailed Beast in Naruto in any way. Each of the Tailed Beasts is born out of the chakra of Ten Tails that the Sage of Six Paths, Hagoromo Otsutsuki, separated from his body. With the Creation of All Things Technique, Hagoromo divided the chakra of Ten-Tails into nine different bodies.

During this time, there was no mention of Zero-Tails anywhere, and neither do the Tailed Beasts remember it. The creature was only showcased in Naruto Shippuden the Movie: Bonds, and never in the mainstream series. The only person who referred to this creature as a Tailed Beast was Shinno, who was the main antagonist of the movie.

The Zero-Tails in actuality is a malevolent spirit, born out of negative and dark human emotions and thoughts of people, who are oppressed. The creature was sealed in the Land of the Sky using a complex sealing technique with a dark chakra. Later, Zero Tails was connected to Ancor Vantian, Sky Ninja’s main base, using several tubular attachments.

The Zero-Tails powered up the entire Land of the Sky and also the powerful laser-like weapons that were capable of wiping the Five Great Nations in an instant. Shinno possessed great knowledge regarding this creature, which is why he was capable of drawing a tremendous amount of dark chakra from it to enhance his overall capabilities.

The only reason behind Shinno’s ability to effortlessly draw the dark chakra from the Zero-Tails was due to the darkness in his heart. The Zero-Tails won’t lend its dark chakra to someone who doesn’t have malice in their hearts. With access to this great source of power, Shinno was able to perform high-level techniques without needing to form hand seals.

Despite being restrained with a sealing technique, Zero-Tails can easily absorb any chakra from external sources, especially the Ancor Vantian special prison cells. Anyone who gets imprisoned in these specialized chambers gets drained out of energy, and that is how the Zero-Tails feeds on others' chakra.

During the fight between the Zero-Tails with Naruto and Sasuke, it was noticed that despite having the overwhelming ability to absorb chakra, the creature retains a very small reserve in comparison to a Jinchuriki. While Naruto voluntarily tried to give away a fraction of Kurama’s Chakra the Zero-Tails couldn't manage to handle it.

If Zero-Tails had been an actual Tailed Beast, it would have easily rivaled Jinchuriki with ease. Moreover, when Zero-Tails tried to trespass on Naruto's mindscape, Kurama responded most violently.