I Have a Passive Skill

Is the world's strongest skill one that requires active use? Wrong! It's a passive skill! What is a passive skill? A passive skill is an instantly activated active skill, an unsuspecting killer move, and the ultimate trump card known only to the dead! Can you explain it more simply? Breathing techniques, strength, perception... Hehe, is that all? Xu Xiaoshou tore through the galaxy with a single sword, shocking the world. ... What the hell do you call this passive skill? Well, swordsmanship mastery.