Here is a video I made to elucidate some weird punching behavior in China Warrior. After playing it for 31 years, I would really love to better understand the underlying punching mechanics so please chime in if you have any better info about how these work.

China Warrior is notorious for how hard it is to pull off the "Super Punch" consistently by simultaneously pressing Right and I. At 1:18 I start trying to Super Punch the boss and, after six attempts, finally land one at 1:30.

At 1:46 I demonstrate that the Super Punch can consistently work by letting yourself be hit 2x and then pressing I.

At 3:36 I also demonstrate something I call a "Machine Gun Punch" that I have never seen referenced elsewhere. It is accomplished by letting yourself be hit 3x and then pressing I.