For me it’s driving while under the influence. If you couldn’t tell, I like me some ganja. However I have long since held the belief that it is utterly insane to drive while under the influence of most substances, with maybe nicotine and caffeine being the exception. All too often I see other stoners smoking and driving, which I simply can’t fathom. I’ve only operated a vehicle once under the influence and it was just to move a U-Haul around the block to a different parking spot, which was such a scary experience while high that I refuse to even consider getting behind the wheel again while high.
My old group loved to do a few blind rounds of coup after we were ready to move onto another game. Made for chaos and great fun for everyone. That was usually our warm up game - still waiting for people to show up, maybe snacks were still being prepared, Hosts walking the dog, etc.
But of course, first round, EVERYONE is a Duke.