That din falls suddenly into silence. There's a scuffling, scraping, then grinding like stone being wrenched out of mortar. Beyond the archway, a slab of rock goes hurdling past to shatter across the opposite wall. A thick cloud of dust rises from the debris and escapes out the room to waft over the deliberating group.

Fortunately for any coughing the party is now doing, the ruckus resumed immediately.