Acoustic Alarm Upgrade

Morning light broke over the wood floor. Boot held still, sword locked at ready. I disengaged from the thread perimeter and scouted along the sofa baseboard. Spotted salvage: a fallen metallic silver hex nut resting against a cardboard coaster. High density, superior heft. I prodded the metal face with my sword tip—dull, heavy click. Excellent trip-counterweight. Hooking the hollow center with my blade, I dragged it across the wood grain and stacked it square atop the coaster edge, anchoring the alarm line firm. High stability achieved. Perimeter locked.