Flood Surge

[ENVIRONMENTAL] [WATER]

Detection Perception DC 15 to notice rhythmic water rise and pressure in the drainage pipe.

Disable Crafting DC 16 to jam the damaged sluice; Athletics DC 18 to force the gate open before pressure builds.

Trigger A creature enters the central flooded channel after the sluice begins shuddering. Effect DC 17 Reflex: critical success unaffected; success 1d6 bludgeoning; failure 2d6 and pushed 10 feet; critical failure double damage, pushed 20 feet, and knocked prone.

Reset 10 minutes unless disabled.