The reason why Ichigos Bankai could not be stolen In Bleach.
Yamamoto hypothesized that it was because Ichigo had only recently mastered his Bankai and it was still in the early stages of development.
Because of their lack of knowledge about Ichigo’s power level, the Wandenreich couldn’t steal his “Bankai.”
This makes sense because Ichigo’s latent abilities were the reason he was recognized by the Wandenreich as powerful enough to make him one of the Specialists.
The Reason Why Ichigos Bankai Could Not Be Stolen In Bleach https://t.co/qt38eUtERH
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In reality, Ichigo is a being who possesses distinctive characteristics from the four major spiritual races known to Soul Society.
These souls such as Shinigami, Hollow, Quincy, and Human. This made Ichigo a divergent entity that does not conform to the restrictions of any individual existence.
In the end, he would have had the greatest innate talents and natural potential for his time period and the spiritual power that human beings could ever acquire.
Ichigo started off with no knowledge of his true origin and power, which is how he managed to use less of his “true powers” to unleash his so-called “Bankai.”
Ichigo’s Bankai was too strong for Shinigami’s powers to be of any use in copying him.
Quincy still proved to be useful because Makoto is a Quincy and Kishirou is able to copy anything from her.
Why Ichigos Bankai Can’t be Stolen
Yamamoto hypothesized that Ichigos Banka couldn’t be stolen because it has room to grow and evolve.
Yamamoto is utterly shocked when Yhwach warns him that in order to steal a Bankai one needs to be sufficiently strong enough to steal it and then demonstrate this by stealing his own Bankai from him.
So that theory is either invalid or unverified speculation. Ichigo versus Arrancar. When Ichigo came out to use his Bankai, his enemy attempted to steal it. It didn’t work
Ichigo vs Quilge
Quincy was a pure-blood and exceptionally powerful. As Ichigo had activated his Bankai, Guilge attempted repeatedly to steal it until he entered his “vollstandig” state.
So far, opponents have tried unsuccessfully to steal Ichigos Bankai. Quincy and Arrancar both tried to steal it but failed (because they are weaker enemies). Why they failed is not yet explained by the story.
Quincy Medallion
This is the device that uses nanotechnology to steal a Bankai and allow the person using it to overwhelm their intended target.
It appears Ichigo alone had immunity when this happened.
My opinion is that Ichigos Bankai was only a “name-only” Bankai.
He didn’t have one up until Aruru forged him with a real shinigami Zanpakuto, making his previous Bankai obsolete.
The swords on the right seem fewer Shinryou than the others. You can see they are manifested by old man Zangetsu, who is currently pretending to be Ichigos Zanpakto (the second to left).
Ichigo’s Quincy swords are an indication that Zangetsu is a worthy Quincy of the highest class.
The Quincy development of the Medallions for the Wandenreich was specifically designed to steal Bankai from Shinigami.
If Ichigis Shikai and Bankai are Quincy powers pretending to be Shinigami powers, then it doesn’t come as a surprise that the Quincys could not steal them.
In short, the medallions are designed to steal power away from Shinigami and not Quincy.