Ren dragged her palms flat across the smooth expanse of the black obsidian wall. She stepped methodically down the outer corridor, sliding her hands over the stone, until suddenly, her right hand met no resistance.
Instead of touching solid rock, her fingers plunged straight forward, disappearing up to her wrist.
Ren's eyes shot wide in wonder. She gasped, quickly withdrawing her hand and staring at her intact fingers. She looked back at the wall. To the naked eye, it looked exactly like solid stone, complete with the same jagged cracks and damp moss as the rest of the corridor. But it was an illusion? A magic trick maybe? A trick of the light?
"Okay, that is really cool," Ren whispered, waving her hand back and forth through the rock.
She quickly glanced up and down both sides of the hallway to ensure no one was watching her. Seeing the coast was clear, she held her breath, closed her eyes, and stepped right through the solid-looking stone.
