Of Jigenryuu - the *one* skill in Satsuma! It's the sword skill used by Ujiki (the corrupted police officer in RK #2). It emphasise that the first slash is also the final one, so you *must* beat your opponent the first time.
In 1863, a radical imperial court offical, Anekouji Kintomo, was assassinated when he was returning to his residence at night. A katana was left at the scene, which was recognised to be the belonging of Tanaka. There were doubts to this, however, for Tanaka was an accomplished assassin, and it's unthinkable for him to be so careless as to leaving behind his katana. Tanaka denied to have assassinated Anekouji when he was arrested, but when the katana was produced, an expression of extreme shock showed on his face. He then snatched up a sword lying nearby, and before anyone could stop him, commited seppuku!
Who assassinated Anekouji? Why leave behind the katana? Why frame Tanaka? What did the shocked expression on Tanaka's face meant? What was so critical that he committed seppuku there and then? Until this day, these questions remain to be mysteries in the history of Japan...