Nage Jiaozhu, Chong Chu Jianghu Le!

Tang Ke, the former leader of the Demonic Sect, had left the martial arts world ever since his cultivation went astray. But he was forced to return when his son went missing. Forgotten by others over the years, working as a poor writer after failing the Imperial Exams, he will slowly grow into the one that was once feared by all... the demon king! "Tell those who respected me, feared me, dreaded me, that the sect leader is back!"

(Source: Bilibili, translated)