Osoroshīken

The Osoroshīken is a specialised, thickened Kiriha Zukiri blade with specialised properties. The blade is capable of generating a protective sphere of chakra around its user when necessary, protecting them from most frontal attacks. Osoroshīken is also capable of using its user's chakra as an extension; allowing it to channel the chakra into an sharp. additional layer around the blade, which lets it land hits on enemies even though they've dodged the blade. Unlike most Kiriha Zukiri, this blade is much thicker and resilient, though Masa Nakamura describes it to weigh no less than a feather. Nakamura is alleged to have killed the famous owner of the blade due to him coveting it, roughly twenty years earlier. Since then, Osoroshīken has become one of the identifying symbols of the terrifying madman's murderous rampages. The blade is rumoured to reek heavily of organs and blood, giving it a rotting, fish like smell.

Trivia

 * Masa Nakamura uses this blade to a much more skilful extent than its actual, former owner and alleged creator.