The Hollow Drum
Past the open door. A vast clearing stretched out. On the timber floor sat a broad, hollow cardboard box, taped shut on top. A new boundary. I charged. Skull down, jaws parted. Wham! A massive, booming hollow thud echoed through the room. The cardboard bowed inward under my snout, resisting with a stiff, springy crunch. The shock shuddered straight through my skull down to my talons. It didn't crack. It rebounded, humming deep and loud. Satisfying. A resonant beast.