As Kohaku's team fight Tsukasa and Hyoga, Senku, Gen, and Chrome tries to figure out a way to make gunpowder. Chrome gets sulfuric acid from the tank, of which is mixed with the nitric acid and glycerin from soap to make nitroglycerin, and subsequently dynamite. This makes Tsukasa's men surrender. Tsukasa and Senku talk out as to why the former wants to make a pure world, when it is learnt that he's doing it for his little sister, Mirai. A flashback is shown of Tsukasa's past; his sister was deemed clinically braindead, thus became comatose. He made it his life's mission to protect her, so he became a boxer at a young age. In the present, Senku wants a truce in exchange for reviving Mirai. Senku and his group goes to the area where her former hospital was. Tsukasa talks about his beliefs and laments on his actions, but won't change his goal. Senku and his crew dig-up Mirai from the area.