We started out by each going into an element and trying to puzzle it out. It turned out not to be entirely a mental exercise, as some people were clearly in elements that disagreed with them very much, and we had to swap around some. My almost-twin from first grade was moved to hide behind some very cluttered corner.
It turned out to be a very clever logic puzzle. We had been thinking of physical elements -- it turned out to be the more metaphorical kind of element -- as in, where someone is "in their element" in something, and the names of the elements all ended with "um" in some way. (I keep thinking that there had to have been "auditorium" around there somewhere, but that's a waking thought. It never had a chance to show up in the dream.)
I can't remember the first one I discovered, but once the person for that element had been discovered, I went around in search of another place to sit. The only unoccupied area left was a thin pink spongy strip, and I hopped up there -- and I discovered that it bounced and flexed, but not in a way that made me scared that I was going to fall off. Experimentally, I tried a hop or something, then, excited, hopped off, and went from standing on the floor to a handstand on the floor to flipped on my feet onto the beam, all with form where I could feel the places it was right, and feel the errors as well. "GYMNASIUM!" I called out in triumph, and beckoned my old elementary school friend Gaia (of the Ginger, Gaia, and Galadriel trio) to come over. We watched her as she performed in her element.
Nearly all of the elements were identified and were on their way to being identified. My old friend my almost-twin was over on the other side of the room, perhaps still hiding. There was one element, though, an area on the west side of the room up in a loft, with a window, that had not yet been identified. One person had gone in, and had stayed in there, and when someone thought to check, he'd been pulled out as a dusty set of clothes full of dusty bones. After that, someone had put up some things over the window -- made the glass appear frosted, put curtains over it.
A group of people were going in now, and the window could not be seen through. I inhaled sharply -- the connection had just come to mind as the last of the exploring party disappeared. "Mausoleum!" I gasped to my roommatesister, who was suddenly there with me, in the way of dreams.
In turn, she gasped. "That will kill them!" she said, and charged into the anteroom, up the ladder, and into the element.
Sure enough, she started hauling out unconscious bodies, elaborately costumed as we all were in the large Room of Elements. I think absentmammoth was hauled out first. I sent her back in to get someone else and dealt with getting the unconscious people beginning to head back to normal. That was her element, sure enough, now that it was identified, because she was unaffected by it.
In the middle of all the hustle and bustle, I woke up.