The walls trembled.
A low mechanical clunk echoed through the chamber.
Thin vertical lines appeared from the center of the dome and extended down to the floor.
A horizontal line followed and cut across them, carving a grid pattern over the entire wall.
Before Ben or Elvira could react, each square in the grid started bulging outward.
The surface turned red.
White spots appeared on the red blocks.
Another horizontal line formed on each cube.
This one twisted and curled into a mouth that stretched into an eerie grin.
Sharp white teeth pushed out from the new mouths.
"Elvira, stay where you are.
I will take care of this," Ben said.
He pulled out his pickaxe.
Hundreds of these block monsters appeared along the walls.
Ben studied them for a second.
They did not seem to have any long range attack, so he did not feel worried.
Seconds passed.
The cube monsters began to slide sideways.
Each row moved in a different direction.
