Jackie Chan (Chien Fu) got his front tooth knocked out by the powerful kick of Jeong-lee Hwang (Lord Sheng Kuan). In the finale, the gap where Chan's tooth was is clearly seen.
First movie in which Siu-Tin Yuen appeared as a wandering eccentric Kung Fu Master. He reprised the same character type in different kung fu movies, one of which is El maestro borrachón (1978), which also features Chan as the leading character, Dean Shek as a bumbling assistant teacher, and Jeong-lee Hwang as the final opponent.
Sheng Fu was supposed to star as Chien Fu, but was refused by Run Run Shaw, head of the Shaw Brothers Studio. This led to Jackie Chan being cast in the role.
At around 1:22, while filming a sword fight, Jackie Chan's arm was accidentally slashed by a sword. He went on fighting, and the footage appears in the film.
Like most movies released in Hong Kong during that time, its original soundtrack is dubbed in Mandarin, not Cantonese. The Cantonese soundtrack was dubbed several years later when Cantonese became the predominant language used in the Hong Kong movies in the 1980s.