Bruce explains to Alfred the particular nature of Kyodai's ransom demand: Yoru is the last living descendant of an ancient master who developed the fighting art, Kiba no Hoko ("The Way of the Fang"). It proved so dangerous that the master never taught it to anyone, and hid the only copy of the art's manual in a secret place known only to his family, who have kept it secret for five hundred years. Since Yoru has no sons, when he dies, he takes the secret with him. Kyodai wants the scroll, believing the knowledge will enable him to defeat Batman, whom he now knows is Bruce Wayne, having fought both of them.
The next morning, Yoru receives instructions from Kyodai. He is to receive a map to the scroll's location in exchange for Kairi. Bruce suggests giving Kyodai a false map, but Yoru says doing so would violate the code of Bushido. Bruce respectfully volunteers to deliver the map.
At the ransom drop, Batman brings the map. He tries to rescue Kairi without giving it up, but Kyodai kicks her off the building's roof, forcing Batman to save her while Kyodai grabs the map. Batman then tries to stop Kyodai, but he escapes.
The map guides Kyodai to a cave in the side of a volcano called Mount Kajiiki, where he finds the scroll hidden in an ancient box. The moment he touches it, however, the aged scroll crumbles to fragments in his hands. Initially distraught, he looks closer and pulls out one intact fragment, which he figures is all he needs.
Later, Batman investigates the cave, and returns as Bruce with the fragments to Yoru, who examines them, and finds that the missing piece gives instructions for the o-nemuri attack – a death touch. Unfortunately, Yoru never read the scroll, so he cannot tell Bruce where the fatal point is, meaning it could be anywhere.
For the next phase of his plan, Kyodai kidnaps Alfred and calls Bruce, ordering him to appear for their final match. Bruce traces the call to Kyodai's hideout, finding it empty, and that Kyodai has destroyed the scroll fragment.
They meet on the slope of Mount Kakiiki, Kyodai apparently not knowing that the local authorities have noticed it becoming active and evacuated the surrounding area. efore they duel, Kyodai compliments Batman on his mastery of stealth, saying he would have made a fine ninja. Kyodai then removes his mask and Batman returns the favor.
They spar, Bruce trying to avoid contact, even as the volcano begins to erupt and lava flows down the side of the mountain. Then Kyodai lunges and jabs his fingers into a spot on Bruce's chest. Bruce groans and falls, apparently dead.
As Kyodai turns away, however, Bruce rises, saying the ancient technique doesn't work. The fight continues, but is interrupted when a lava flow splits the ground between them. Kyodai is left trapped on a little islet of rock. Bruce throws a line on a Batarang to Kyodai, telling him to use it to spring over the gap. Silent, Kyodai kicks the batarang into the lava, then bows to Bruce with utmost respect. Another surge of lava hits the rock, throwing up a cloud of smoke between them. When it clears, Kyodai is gone.
Bruce and Alfred make their way to safety. When Alfred asks how he survived the death touch, Bruce pulls a small armor plate from under his costume and explains that he examined the practice dummy in Kyodai's hideout and found a soft spot that Kyodai had jabbed with his fingers many times.
Bruce bids goodbye to Yoru, who asks him to be sure to pass his respects along to Batman. In a moment of self-doubt, Bruce says that Batman is as much a ninja as Kyodai, but Yoru tells him that because Batman showed mercy to his enemy, and resisted the temptation to use the knowledge of the death touch, he is a true samurai. Bruce thanks his old teacher and departs.
