The Maw of Diminishing Space
A stone chamber that appears perfectly normal until the threshold is fully crossed, at which point the entrance vanishes and the walls begin to contract with impossible speed.
The Maw of Diminishing Space
Defenses
Detection
“A 20-foot by 20-foot square room with walls of polished obsidian. A single, tarnished silver key sits on a stone pedestal in the exact center of the room.”
Standard Engagement
A creature picks up the silver key or four creatures enter the room.
None
The room resets after 1 hour, or immediately if the spatial anchor pedestal is destroyed.
The room snaps shut. Every creature in the room takes 4d10+10 bludgeoning damage as the walls rush toward the center. A DC 21 Basic Reflex save reduces the damage. On a critical failure, the creature is also Restrained until they can escape (DC 20) or the hazard is disabled. The room remains only 5 feet wide until it resets.
When the hazard triggers, the door is replaced by solid stone. This is an illusion backed by physical transmutation; it requires a successful Dispel Magic (level 2 or higher, DC 20) to reveal the door for 1 round.
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