Fans of Wolverine comic books know that he has, from time to time, wielded a Murasama blade, forged with a part of his own soul, blah blah etcetera. Basically, it's called upon from time to time to do those pesky jobs six indestructible claws cannot. Like this:
Sabretooth learns the hard way that discretion is the better part of valor.
Imagine my delight, then, while reading Ben Thompson's relentlessly excellent Badass: A Relentless Onslaught of the Toughest Warlords, Vikings, Samurai, Pirates, Gunfighters, and Military Commanders to Ever Live that Murasama blades have a historical pedigree:
"One of Japan's greatest and most brilliant armorers, the mentally unstable Sengo Muramasa, produced powerful swords that could cut through even the thickest iron and steel with ease but were considered unlucky, violent, and incredibly bloodthirsty. These cursed blades hungered for death - if the weapon's owner failed to draw the blood of his enemies in a timely manner, the sword allegedly would drive him completely kill-crazy, forcing him to commut murder or suicide to appease the demonic spirits that haunted the weapon."
Unfortunately, whether or not an actual Murasama blade could in reality kill a self regenerating mutant remains (for the moment) untested.