I don't know. But it seems like she's stronger than most of us expected and she's is stated as the first Kempachi. I think we will know why when she trains Zaraki.
Thank God you changed Kenpachi and Zaraki around. I was about to correct that. xd
OT: Maybe to keep her power a secret for the next invasion? Idk...
bcos yamamoto told her to stay put ... it was his last order or sumthing like that ...
But we know now that she is one of the five war potentials.
Are you referring just to the Quincy invasion? If so, then it's because Yamamoto told her to stand back and heal the wounded.
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No we don't
Yes well I know. And I am willing to bet on it. And the reason why well there has never in soul society history ever been a medic captain class with kenpachi type ability as well this will be enough to be one of the five. Also if zaraki was considered one then unohana is definitely one.
When she fights, there is no stopping and she goes into a frenzy state.