From Pathfinder #173: Doorway to the Red Star, which isn't enabled.

Flensing Chute

HAZARD 12

Stealth +25 (master)

Description The stairs collapse into a downward spiral.

Disable DC 35 Thievery (master) to decouple several mechanisms barely accessible through gaps between the shifting risers, or DC 38 Perception to note which stairs have slightly different wear patterns to know which ones are safe to step on

AC 10

Change to Chute

Trigger A Small or larger creature approaches within 20 feet of the top of the stairs

Reaction The stair risers shift downward, forming a steep ramp while exposing lines of razor-sharp blades.

All creatures on the stairs must succeed at a DC 32 Reflex save or tumble down the chute, taking 2d6 bludgeoning damage + 4d12+26 slashing damage, and landing Prone in area A4.

Reset The flensing chute resets automatically.

Pathfinder #173: Doorway to the Red StarOGL