Introduction Baduk Classic : The Profound and Mystrious(현현기경, Xuanxuanqijing) was written between 1347 and 1349, during Yuan dynasty. It is marvelous that a life & death exercise book written several centuries ago is still loved by many amateurs and professionals. Moreover, each exercise has its proper title, which makes the exercise more mysterious and interesting. It is said that nothing is better for improving baduk skill than solving life & death exercises. They teach us vital points, keymove, and marvelous sequences, as well as help improve reasoning power and perseverance. This book has some exercises that are so profound and abstruse that even professionals cannot solve them with ease. We translated ‘Hyunhyungigyung’, published by Hyunhyungak in 2000. Errors in problems and answers were corrected, and some reference diagrams were added for very hard problems. We hope this book will be of help-at least, a little bit- for you to improve your baduk skill.