They soon began brewing, but that didn't seem to soften Snape's mood. He swept through the dungeon, praising the Slytherins and brutally critiquing the Gryffindors. Snape was just crowing about Malfoy's preparation process when Neville yelled in pain—Seamus's cauldron had somehow melted into a misshapen blob, and a caustic red liquid had gushed out of it, drenching Neville and spreading across the floor. Everyone jumped up onto their stools, trying to avoid becoming the next victim of the potion.