why didnt Sammo and Yuen Biao be in this film

They were making the film 'Eastern Condors' at the time and could not partake.

Though I would have loved to see them in this film, they really didn't have much room in the sequel. Yuen Biao maybe but Sammo was just a friend of Jackie's character who kinda was mixed up in the story and action, to have him in the sequel wouldn't make that much sense.

Mars and that other guy from Project A were still in the film, so despite two of the three brothers missing in action, it was a very good sequel that stayed true to the source material of the first one.

"Don't look down on yourself, just because other people do."
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