The attacker makes an opposed roll with his martial arts skill level, target number is the opponent's strength. The opponent can make a Body test to reduce the damage. If the attacker rolls more successes, the lock holds. The attacker can release the lock at anytime without causing damage to the opponent. An opponent cannot perform any actions while in a joint lock except try to break the lock.
Joint locks are quit painful.
No damage is taken. He can only make one attack, unless there are two targets within one meter of each other. All attack damage codes are one higher when performed in a leap attack. Even though the attacker can make only one attack in a turn with a leap attack, he may still defend normally. The opponent can make a Body roll to reduce the damage.