In Bleach, the strongest enemies that the Shinigami have ever faced are the Quincy, who got very close to destroying Soul Society itself. In most of their battles, the Quincy mercilessly overpower the Soul Reapers, and there is one clear explanation for that, which however does not make much sense after deeper scrutiny.
Shinigami and Quincy are described in Bleach as two radically opposed existences. The Shinigami, or Soul Reapers, are particularly powerful souls that, through training, achieve a high level of Reiryoku (spiritual power) and take on the duty of purifying Hollows and accompanying other souls through the cycle of transmigration. On the other hand, Quincy are living beings who have a particular affinity for spiritual energy. They can perceive Hollows and have a high level of Reiryoku, but the one quality that sets them aside from other humans is their ability to absorb and manipulate Reishi (spiritual particles) from the atmosphere.
Reishi are the foundation of every spiritual creature in Bleach, and they compose the bodies of Shinigami and everything that exists in Soul Society or Hueco Mundo (the land of the Hollow). Quincy can manipulate these particles for a variety of effects, including creating spiritual weapons, simulating the effect of Shinigami’s spells, and other powerful abilities like their ultimate form, Vollständig. During The Thousand-Year Blood War arc in the manga and its recent anime adaptation, the Quincy attack Soul Society, after hiding and preparing for a millennium, and they almost annihilate the Gotei 13 guards and destroy the Seiretei entirely. The reason why they attacked the Shinigami in their own home is that Quincy are more powerful in environments with higher concentrations of Reishi such as in Soul Society or Hueco Mundo, where they can absorb as much Reishi as they want.
Shinigami Should Be Able To Use Reishi Just Like Quincy Do
While Shinigami entirely rely on their Reiryoku, which is an inner source of power, the Quincy make no distinction between Reishi and Reiryoku, meaning that have an almost limitless source of energy compared to the Soul Reapers. This obviously gave them an edge in the fight, as seen during the merciless slaughter of Shinigami, including Gotei 13 Captains, during the Quincy’s attack on Soul Society. Reishi manipulation is also the basis for the Quincy’s most powerful anti-Shinigami technique, the Wandenreich Medallion, which allows them to steal a Soul Reaper’s Bankai (which is also made of Reishi). The series, however, does not explain why the Quincy are the only ones who can use this technique. In fact, Shinigami’s bodies are made of Reishi, just like everything else in their world.
The Soul Reapers, then, should have a much bigger attunement to Reishi than Quincy, who are still humans, or at least they should be able them as an energy source too. For example, Captain Kurotsuchi, who has studied Bankai in-depth, is able to forge one from scratch using his scientific prowess, so other Shinigami should be able to manipulate Reishi too. Like many other aspects of The Thousand-Year Blood War, the Quincy’s attunement to Reishi remains a mystery. Bleach author Tite Kubo wanted to end the series as soon as possible due to poor health, so he left a lot of plot threads hanging. Fans of Bleach can only hope that the ongoing anime adaptation of The Thousand-Year Blood War will answer this and many other mysteries regarding the Quincy and the Shinigami that their favorite series left behind.
