Earthquake

The ground shakes violently. All creatures in the area take 6d10 bludgeoning damage with a DC 30 reflex save. On a critical failure, the creature falls into a 40-foot-deep fissure opened by the tremor. They can attempt to Grab an Edge (DC 30 to prevent the fall, with a –2 circumstance penalty due to the moving ground). A creature that falls takes an additional 20 falling damage, is knocked Prone, and must be rescued from their predicament by another PC taking one action to pull them free. If any creatures are still in fissures due to previous tremors, they automatically get a Failure on this save.