Just as fair warning, if you wear football shoulderpads on Halloween, you should be prepared to be punched... quite a bit. This includes being punched by people who simply do not realize that shoulderpads protect the shoulders and not the stomach.
Hot guy I don't know: (excitedly watching other people punching me in the shoulders) Can I punch you?
Me: Sure, just watch out: there's a little metal piece h—
Hot guy I don't know: (punches me in the stomach)
Luckily, my six years of childhood karate training adequately prepared me for this moment, as I had instinctively instantly reacted by tightening my muscles. I came out unharmed, just very surprised that (1) I had just been punched fairly hard in the stomach and (2) despite this I felt completely fine.
I declined hot guy's apologetic offer to let me punch him back. He was a UPS driver, and it's probably best to stay on a UPS driver's good side; otherwise, he could decide to start requiring signatures on delivery or something equally horrifying. (Had I only been thinking more quickly, I would have instead requested a staged photo to go along with this amusing anecdote.)