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This technique essentially hardens the hair on the user's head and shoots it continuously at the enemy. At the same time that Jiraiya kneads the chakra needed for Senjutsu and fires the hair needles, Fukasaku and Shima activate Jiraiya's hair roots causing the hair to grow at an accelerated rate thus making limitless rapid-fire possible. The sharpened points of the hair can turn the target's entire body into a pincushion. The sheer speed of this technique makes it the fastest attack with the widest range possible in Sage Mode to Jiraiya.
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