The series follows Mutsu Tsukumo, a young martial artist, in his pursuit of perfection. He takes on more and more challenges, and stronger and stronger opponents as the story progresses. His martial art is one handed down through the generations called "Mutsu Enmeiryuu", which he proudly boasts that in over 1,000 years has not been defeated even once. It is a perfect combination of strikes, joint locks, throws, ground-fighting techniques, and special "hissatsu waza" (one-hit kill techniques). Source - Tapanime.