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From Pathfinder Dark Archive (Remastered), which isn't enabled.

Shrinking Hall

HAZARD 2
Stealth +8
Description This hallway is designed to shrink as creatures traverse it, making access to the door at the hall's end impossible.

Disable DC 21 Thievery (trained) to jam the scales built into the floor


Shrink
Trigger 100 pounds of weight or more is placed on the hallway's floor

Effect The hall's last 40 feet of walls angle inward, causing the hall to shrink and contract down, reaching 6 inches in height and width at the hall's far end and completely blocking access to the hall's exit door for anything but a Tiny creature Squeezing.
Reset After 10 minutes without weight being placed on this hall's floor, this trap resets, returning the hall to its original size.
Pathfinder Dark Archive (Remastered)ORC