All he did was one little tap(!) & his foe's grip in their blade's disrupted by micro-shockwaves that affect their hand axons, disarming them That was how easy it was for him to win any duel Oh? You don't use weapons? Welp, you can't use your hands anymore This technique affected the very neurons that allowed movement, so it is easy to paralyze any body part even if it's not for disarming your foe