Audio problem: When Jet Li is using the frying pans as weapons at the start, he hits different people in different places on the body, but gets the exact same sound. (00:05:40)
Audio problem: When villain says "Well done, I'm impressed" the words don't match what he says and are a clear overdub. (00:34:10)
Answer: "We keep it light" refers to their mood. They joke around and tease each other and have fun. "Till we go dark" is when they get serious for killing. "We go pitch black." Meaning as dark and brutal killing machines as possible.
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