The reason for the aforementioned leaf-cutting abilities of the Masamune and Muramasa blades might be as follows (although the actual name of the smith was Muramasa, Bakin was notorious for renaming famous people in the Hakkenden and sneaking them in):
Masamune was great swordsmith in Japan, and a well-known philosopher I believe. His works with the blade were so masterful his student Muramasa wishes to recreate his work, but failed due to shortcomings on the most important martial princicple.
In the Japanese bujutsu there is a saying: satsujinken katsujinken. Roughly translated this means 'The sword that kills, the sword that gives life'. This principle donates the entire word martial (bu, or 'stop the spear') in that a martial artists goal is to preserve life with his skill, never to take it.
Masamune knew this, but Muramasa did not. For this reason he did not have the insight on the blade as his teacher did, and could therefore never accomplish the same skill in his own work.
Because he assumed the blade was for death alone, his swordwork as always been pulled to the satsujinken side of the equation, his blades always wanting blood and never serving their true identity.
The above could denote why the Muramasa is deemed 'cursed', and such a 'powerful' blade is treausred for more than just being the ruling staff of the Kanto. Back to Miscellaneous Items