Now that I think of it there was actually two swords and I misspelled the name... It's actually Muramasa...No i in it... The first also known as the Black Blade was forged with a piece of Muramasa's own soul and it also had his madness. The wielder could be overcome with the blades influence which Wolverine did the short time he had it. The Silver Samurai took up the blade and was actually able to us it with no ill effects, but it was never in another story after that. One could assume that Harada still has the blade somewhere...<br/><br/>The second was made especially for Logan using a piece of Logan's soul... It was able to slice apart a S.H.I.V.A. robot on a molecular level and even cut through one of Cyclops's optic blasts sending it different directions. (I know different writers and everything, but still a totally gnarly concept) It was given to Scott to keep safe, but since then Logan buried it in some unknown location...