A failed "bwah!" moment happened to a GM friend of mine who was running a D&D(ish?) campaign. The party came across an enormous room that was completely empty. But the entire floor responded to "detect trap" spells. They spent hours of real time trying to figure out what the heck was up with the room (before setting foot on the trapped floor) before giving up and backtracking.
My GM-friend was crushed. You see, the floor was an elevator platform that, when the party stepped on it, would have taken them on an express ride straight down to the chambers housing what the elevator was intended to carry: a fully-armed, lightly-sleeping late-mark Bolo. Yes, he brought a Bolo into a D&D campaign. He apparently had some epic plans for said Bolo. And all that effort, wasted.
My GM-friend was crushed. You see, the floor was an elevator platform that, when the party stepped on it, would have taken them on an express ride straight down to the chambers housing what the elevator was intended to carry: a fully-armed, lightly-sleeping late-mark Bolo. Yes, he brought a Bolo into a D&D campaign. He apparently had some epic plans for said Bolo. And all that effort, wasted.