Meh, I'd probably respond like Gordon Freeman.
Your incredibly inept neighbor possessing a rail gun cannon and the off chance it is ready to go and he's about to fire it, withgout looking where it is pointing which is right at your house and toward your gas and plumbing mains.
"I wasn't counting cards, I was cheating."
"Ugh. you give me hives."
"It's Tee-revor time!!!"