Possible Clues:

• Martial art with a belt system
• Japanese word that means empty hand in English
• King leads a charge to create defensive system
• Sport with chops
• Martial art Ken attempted initially with speed
• Martial art featured in "Cobra Kai"
• Ace, right to engage in major royal sport
• Black belt discipline
• Martial art whose name means "empty hand"
• "Cobra Kai" practice