Dreams of karate represent fighting, that you are coming into your power, and that you have a desire to break through obstacles in your ability to defend yourself. This is also a dream about mental discipline, commitment, diligence, strategy and focus.
A black belt is a sign of mastery in art of defending yourself, and a white belt is a sign of a novice. Consider the feeling tone of this dream.... Strangest Dream Explanations
If your dream involved others demonstrating or using this system of self-defense, you should be prepared for a surprise obstacle to your long-range ambition or plans. But if you were learning or doing karate yourself, you can expect your current affairs to flourish.... My Dream Interpretation