Don't Mess with That Old Man, He Preaches by Killing

Xu An traveled through time and became a skinny old man, and at the same time awakened the killing system. Since then: On the top of the martial arts, proud of the world, I am here to control the mountains and rivers; The king of troubled times, the emperor among men, seeing me Xu An is like seeing the sky! It's easy to shake a mountain, but it's hard to shake me!