From Pathfinder Claws of the Tyrant, which isn't enabled.

Decrepit Bridge

HAZARD 2

MECHANICAL

Stealth +4 (trained)

Description The 30-foot-long, 10-foot-wide bridge groans under the weight of those who cross it.

Perilous Sway

Trigger A Medium or larger creature Strides 10 feet or more in the bridge's area

Effect All creatures on the bridge must attempt a DC 18 Reflex save.

Critical Success The creature is unaffected.

Success The creature is Clumsy 1 until the beginning of its next turn.

Failure The creature falls Prone.

Critical Failure The creature falls from the bridge, landing in the ravine 20 feet below.

Collapse

Each time the decrepit bridge triggers its Perilous Sway after the first, attempt a DC 5 flat check. On a failure, the bridge collapses. All creatures on the bridge fall 20 feet into the ravine, taking falling damage normally (10 bludgeoning damage).

Pathfinder Claws of the TyrantORC