I am abolutely stunned.
...
I'll be damned if this isn't the best writing I have seen Kubo do in the complete Bleach series... It has completely reinvigorated my suspension of disbelief. I know it will be crushed like a bug later on, and I know he often writes crap, but color me impressed. this chapter is awesome!
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her transformation was obvious, but beyond that not too obvious, also the reason why stuff works or happens is quite important. It serves as a resonable explanation of why division zero exists. It's like an honorary position where people are actually immensly powerful as a result, not as a prerequisite. (allowing Yama-yii to still be the strongest shinigami ever around). And before peopel pointing out Yama-yii created a lot of stuff, maybe he didn't want to pension.
I will hazard a guess that the next stage is metalworking (surely if this guy created zanpakuto they will get it back) and the hero reforging his/her sword is a common trope in these kinds of situations.