Gwen can! And sees a looming monster - wait, no, that's not quite right. A Magnificent chimerical beast, shimmering ivory and golden coils, rising up into the air and looking around, over Thistle and Briar (who, she will later argue, is NOT COWERING.)
But as the Beast exhales, the air in the plant clears - the smoke and sulfur smell of the fireworks, and the lingering fetid odor of the sludge, they fade and the air is refreshed.