Upgrade in the Martial Arts World

The orphan Zhang Nan plays a game and travels to the world of martial arts. This is a real martial arts world, but everyone has a health bar on their head. What the hell is this? "Don't mess with me. As long as the mission is sent out, I will kill you. And if I kill you, I will level up!" "Tch, don't believe it!" "Kill him!" "Ding dong, mission:..." Zhang Nan drew out his long sword and slashed randomly! "No zuo no die why you try!" Sorry, I upgraded again!