Personally, I think it would be better for you to just beat them up as if you were sparring, ignoring the rules. Sure, you'll lose, but they'll be broken in half, and that's a moral victory, at least.

At the same time, just doing Wing Chun doesn't mean you'll stomp them. Everyone thinks that their style is oh-so super lethal, even if some people are wise enough to not actually say it. Find a good balance between confidence and humility, or you might be surprised.

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Moderation In All Things