The walls trembled, a low mechanical clunk echoing through the chamber. Many vertical lines appeared from the center of the dome, then extended downward all the way to the ground. A horizontal line followed, carving a square pattern across the entire wall.
Before they could react, each square started shifting outward. The surface turned red, followed by a pattern of white spots appearing over it. Another horizontal line formed, but unlike the ones before that cut through the concrete, this one twisted into a mouth. It curled upward, stretching into an eerie grin. An array of sharp, white teeth emerged from it. "Elvira, stay where you are. I'll take care of this," Ben muttered, pulling out his pickaxe.
