The The of Squad 0 were chosen for creating something fundamental to Soul Society. They’re also the most powerful Soul Reapers in the setting, their combined power suring the entirety of the Thirteen Court Guards; the anime further reinforced that by revealing that the of Squad 0 have to place a seal on their powers because fighting at full strength would destroy the three realms of Bleach’s universe.
Squad 0 has done a lot to establish themselves as some of the strongest characters in Bleach, especially in the Bleach: Thousand-Year Blood War anime. At the time of writing, many of Squad 0 still haven’t had their abilities fully explored, even with how much the anime has expanded on them. Still, there’s a lot to discuss about each character simply with what’s already been established in the anime and manga, and with any luck, future installments of Bleach will continue to add to their characters.

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Tenjiro Kirinji
The 1st Officer of Squad 0 is Tenjiro Kirinji, the Holy Guardian of the East. Kirinji is known as the “Hot Spring Demon” for his special hot springs that can heal fatal wounds for anyone strong enough to withstand them. Kirinji is also the greatest healer in all of Bleach; not only was he Unohana’s master, but he was the one who invented the healing arts of Kaido, which ultimately granted him entry into Squad 0.
Kirinji’s Shikai is Kinpika, a blade attached to a long wooden pole with incredible striking power and the ability to create blinding flashes of golden light. Kirinji also fights with incredible high-speed movements, his mastery of Shunpo suring even Suì-Fēng’s and earning him the nickname “Lightning-Fast Tenjiro”. Additionally, he can weaponize the water from his hot springs to burn enemies on , and if not that, they can be used to heal him and his allies amid battle. Kirinji's Bankai has not been revealed yet.
Kirio Hikifune
The 2nd Officer of Squad 0 is Kirio Hikifune, the Holy Guardian of the South. Also known as the “Ruler of Grain”, Kirio was the previous captain of Squad 12 before Kisuke Urahara, making her the most recent addition to Squad 0. Kirio was inducted into Squad 0 for creating the artificial souls that Soul Reapers use to inhabit their gigais while in the realm of the living, and they formed the basis for advanced Mod Souls like Kon and the trio of Lirin, Kurodo, and Noba who were exclusive to the anime.
Kirio’s Shikai takes the form of a giant spoon, but at the time of writing, its name and abilities have yet to be revealed. Beyond that, Kirio specializes in tools that deal with manipulating someone’s spiritual pressure, most notably food that greatly restores someone’s power upon consumption. Not only that, but she can create powerful tree branches called the Cage of Life that absorb the energy of anything they come into with, making them virtually indestructible.
Oetsu Nimaiya
The 3rd Officer of Squad 0 is Oetsu Nimaiya, the Holy Guardian of the West. Also known as the “God of the Sword”, Nimaiya is the one who created the Zanpakuto, and he creates every Asauchi, the base form of the Zanpakuto, that a Soul Reaper bonds with before developing their personal abilities. Considering that Zanpakuto have always been an established part of the history of Soul Reapers, it can be assumed that Nimaiya is one of the more senior of Squad 0.
Going right along with his moniker of “God of the Sword”, Nimaiya is incredibly skilled in combat, as he was able to single-handedly defeat Yhwach’s Schutzstaffel before their empowerment by the Auswählen. While Nimaiya’s personal Zanpakuto has yet to be shown, while fighting the Schutzstaffel, Nimaiya used a Zanpakuto called Sayafushi, a blade that was so sharp that it could only be contained within a special jelly-like substance. Nimaiya considered it a failure for not meeting one of the basic requirements for a sword, but it was still shown to be a powerful weapon, nonetheless.
Senjumaru Shutara
The 4th Officer of Squad 0 is Senjumaru Shutara, the Holy Guardian of the North. Also known as the “Great Weave Guard”, Senjumaru created the shihakusho, the black uniforms that all Soul Reapers are shown wearing. Senjumaru’s capabilities as a seamstress are also great enough for her to infuse the Oken, the bones of the Royal Guard, into someone’s clothing to give them enhanced durability and, as shown in the anime when Byakuya fought NaNaNa Najahkoop, a resistance to certain energy-based attacks.
Senjumaru’s Shikai is Shigarami, a sewing needle that has high piercing power and allows her to utilize many sewing and cloth-based abilities such as turning someone’s clothes into a self-destructive weapon, creating illusionary tapestries, and creating cotton that can heal deadly wounds. Senjumaru's incredibly powerful Bankai is Shatatsu Karagara Shigarami no Tsuji, a giant sewing room that traps her opponents in tapestries that assault them with a variety of different attacks. The attacks suffered by Uryu, Haschwalth, and the Schutzstaffel foreshadow their fates seen in the manga, so Senjumaru’s Bankai likely works by assaulting people with attacks that reflect something they’re fated to deal with in the future.
Ichibe Hyosube
The final member of Squad 0, and also their leader, is Ichibe Hyosube. As the Manako Osho i.e. “Monk Who Calls the Real Name”, Ichibe was the one who created names for everything in Soul Society, and he even incorporated this into his fighting style. In addition to creating seals that apply the effect of whatever kanji is written on them, Ichibe can reduce the power of something by shortening its name and even come back from the dead just from someone saying his name. Ichibe also fights with giant spiritual hands that mimic his movements and strike with incredible force.
Ichibe’s Shikai is Ichimonji, a large calligraphy brush with a blade at the end of it. Anything Ichibe strikes with Ichimonji is dyed black and loses its name, thus depriving it of its power, and Ichimonji can draw on anything black in the world to power its ability. Ichibe’s Bankai, which he refers to by the older name of “Shin’uchi”, is Shirafude Ichimonji, which lets Ichibe rename anything that had lost its name to his Shikai and grant them the properties and abilities of the new name. These abilities were enough for Ichibe to overpower Yhwach, and he would have won had Yhwach not reclaimed the power of The Almighty.
Between their placement in the lore and their explicit feats, Squad 0 are some of the most unique characters in the series and also some of the strongest. This is especially true in the anime adaptation of Bleach: Thousand-Year Blood War, as it added a lot of content to better present Squad 0 as the deadly force they were supposed to be, especially Senjumaru. There’s no telling what sort of changes the anime will continue to make going forward, but with any luck, it will continue to give Squad 0 and other characters the level of attention they did not receive in the manga.