I Never Thought I Would Be so Strong

Ever since Yun Che traveled to a world where humans could burp at any time, Yun Che had been thinking about one thing: why did he become so strong? There was no god-level combat skills to learn, no heavenly descending system, and no super magic weapon. After traveling through time, he became inexplicably invincible. Any opponent you encounter will be defeated with one punch. Yun Che was confused, why on earth, why on earth was he so strong?