The book 'The Dominator of the City' fits the information you provided! The main character, Zhang Zheng, returned to the city after disappearing for ten years and became the overlord. He obtained the superpower of the special technique and was known as the Great Thunder God. He stepped over the corpses of his enemies in Control, controlling everything with his powerful strength. He had a domineering demeanor. If you like this kind of urban supernatural novel, you might as well try "The Supreme Overlord of the City". It might not be enough for you. I hope you like this fairy's recommendation. Muah ~😗