The Xros Heart boys join the school's kendo club for the regional tournament and after winning a match, they find that they are being observed by Musashi Kenzaki, a student from a rival school. Later, Musashi ends up in the DigiQuartz and meets Kotemon who takes him as his pupil. Some time later, a mysterious figure starts challenging members from adult kendo clubs throughout the city and beats them to the point of shredding up their clothes.