I have come up with the concept that these unique katanas are dropped by a samari who you can encounter on you travels once defeated in a sort of minin boss battle he will give you these three katanas and become and npc. The fighting style the player will be able to engage with will be as follows 2 katanas one in each hand these are for attacking the third one is poitioned in the players mouth and acts like the shield sword.The npc can give you training in order for your skills with these lehgendary 3 katanas can progress until you become the best swords man possible. Now for those that have any input discuss.
Ah right yeh I thought it would to be cool to heve an idea based upon the three sword fighting concept.