Child's Sword is a sword that Seong Mi-na once gave to Yun-seong. Upon close examination, the words 'For little kids' have been engraved onto an inconspicuous place. In other words, she'd been treating him like a child when she gave it to him. It is completely ineffective as a weapon, but perhaps it will cause opponents to let down their guard. Child's Sword appears as Yun-seong's joke weapon in Soulcalibur II & Soulcalibur III.