If Zaraki had anything along the lines of a shikai or Bankai....he'd be too powerful in my opinion. He could already
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Fight on Par with Nnoitra and his Strongest-of-all-espada heirro (iron skin) just by "adjusting"
And he nearly killed Ichigo in the first encounter in Soul Society. I mean, without Zangetsu Ichigo woulda died. Of course, Ichigo's on the deathbed on a regular basis

Anyways. I can't wait for the next chapter either.