This form of Karate takes on all comers, the instructors and it's students all must have taken part in sparring. Unlike other forms of Karate, Kyukushin demands the black belts spar without any gloves or safety gear on. Each fighter is expected to be not only strong, but be able to take the hits as they come, making this martial art both dangerous and difficult to master.
Today Kyukushin has splintered into many groups, however finding the real form of Kyukushin only involves sparring with the instructor. Most instructors of Kyukushin will accept to "demonstrate" to the student in plain clothes if they are a beginner. In theory a competent instructor would be able to knock a novice down with just one hit. It is not common for a instructor to refuse a request for a demonstration, as this would spoil their reputation.