Isshin use Getsuga!
Oh, I understand nothing.
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Оh, No, I know!
Me on this phrase Isida Ruuken ==> Isshin has pushed: "You have restored the forces?"
It in its first occurrence in the form of captain Shinigami)
So: Small Ichigo exhausts from daddy all force, and it becomes a part him, therefore one remains in Gigai, and another can see phantoms.
Then, years through 15, Ichi meets Rukia, exhausts from she all forces to wake the abilities, which he has exhausted from the daddy.
Fans of Rukia have truly noticed: Appearance of Sode no Shirajuki and Zangetsu NOT in Shikkai, and it is simple in the form of a sword, differ only with the sizes. Colour of the Handle, a kind guard, all at them is similar. Kubo said, what this force of Ichigo - at most Rukia.
More shortly, this all Getsuga also speaks.)))
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Probably, technicians of shinigami are descended?
Then I can dream about Zangetsu with the blue handle and guard similar on six-petal Gibiskus, ne?)))