Our characters had been captured by sahuagin, and we were supposed to do things to impress them. Then they poisoned us and told us to make an antidote. None of us had any of the relevant skills.
So the DM tells us what ingredients we have to work with, then starts threatening us with death if we don't do things to them (and this is the RPGA where treasure is super allocated and death is permanent when you are poor). Some part of the "challenge" was that we were supposed try super hard, but we didn't know that.
So one guy got weepy out of sheer frustration because the character he had been bringing to the RPGA events for years was going to get arbitrarily killed because his personal knowledge of poison-making was lacking.
In retrospect, I find that amusing. I recall a convention where one table (in a room full of tables and over a hundred people) was running a scenario with several bards. The DM tried to insist that the player who was playing a bard actually stand up and sing when his character was using a bardic ability.
For some people, that can be very entertaining, but for others who can't sing, are shy or have acute stage fright, it's very frustrating. It was also very disruptive to the rest of the room. As far as I'm concerned, it's a case of the DM stepping over the line.
As for the antidote incident, even if no one had any relevant skills, the 'solution' would have been just to make an Intelligence check or else start randomly mixing incredients. "Red powder that tastes like moldy cheese? Sounds like the right ingredient!" It would then have fallen to the DM to resolve the scene regardless of whether the characters/players actually mixed the ingredients correctly.
I suppose an alternative, too, could have been to use a completely unrelated (probably) skill. "I'm going to use my Handle Animal skill to mix up the correct ingredients." If the DM ruled that the DC for such was 150, then when all the characters tried the same thing and failed, he MIGHT have gotten the message.
Of course, it's a lot easier to point this out NOW... not so easy at the time I'd wager.
"Blue flowers, red thorns, blue flowers, red thorns..."