When you cast _earthquake_, an intense but highly localized tremor rips the ground. The powerful shockwave created by this spell knocks creatures down, collapses structures, opens cracks in the ground, and more. The effect lasts for 1 round, during which time creatures on the ground can't move or attack. A spellcaster on the ground must make a Concentration check (DC 20 + spell level) or lose any spell he or she tries to cast. The earthquake affects all terrain, vegetation, structures, and creatures in the area. The specific effect of an _earthquake_ spell depends on the nature of the terrain where it is cast. _Cave, Cavern, or Tunnel_: The roof collapses, dealing 8d6 points of damage to any creature caught under the cave-in (Reflex DC 15 half) and pinning that creature beneath the rubble (see below). An _earthquake_ cast on the roof of a very large cavern could also endanger those outside the actual area but below the falling debris and rubble. _Cliffs_: _Earthquake_ causes a cliff to crumble, creating a landslide that travels horizontally as far as it falls vertically. Any creature in the path takes 8d6 points of bludgeoning damage (Reflex DC 15 half) and is pinned beneath the rubble (see below). _Open Ground_: Each creature standing in the area must make a DC 15 Reflex save or fall down. Fissures open in the earth, and every creature on the ground has a 25% chance to fall into one (Reflex DC 20 to avoid a fissure). The fissures are 40 feet deep. At the end of the spell, all fissures grind shut. Treat all trapped creatures as if they were in the bury zone of an avalanche, trapped without air (see Environment for more details). _Structure_: Any structure standing on open ground takes 100 points of damage, enough to collapse a typical wooden or masonry building, but not a structure built of stone or reinforced masonry. Hardness does not reduce this damage, nor is it halved as damage dealt to objects normally is. Any creature caught inside a collapsing structure takes 8d6 points of bludgeoning damage (Reflex DC 15 half) and is pinned beneath the rubble (see below). _River, Lake, or Marsh_: Fissures open under the water, draining away the water from that area and forming muddy ground. Soggy marsh or swampland becomes quicksand for the duration of the spell, sucking down creatures and structures. Each creature in the area must make a DC 15 Reflex save or sink down in the mud and quicksand. At the end of the spell, the rest of the body of water rushes in to replace the drained water, possibly drowning those caught in the mud. _Pinned Beneath Rubble_: Any creature pinned beneath rubble takes 1d6 points of nonlethal damage per minute while pinned. If a pinned character falls unconscious, he or she must make a DC 15 Constitution check or take 1d6 points of lethal damage each minute thereafter until freed or dead. #### Mythic Earthquake **Source** [_Mythic Adventures pg. 92_](http://paizo.com/products/btpy8ywe?Pathfinder-Roleplaying-Game-Mythic-Adventures) Increase the damage dealt to structures by 10 points of damage per tier. Increase the damage dealt by cave-ins and landslides to 10d8 points of damage. Increase the damage dealt to those pinned beneath rubble to 1d10 points per minute. Add your tier to the DC of concentration checks and Constitution checks attempted as a consequence of this spell. **Augmented (8th)**: If you expend two uses of mythic power, the spell lasts for an additional round and the spread’s radius increases by 20 feet. Each round this spell is in effect, on your turn you may expend one use of mythic power to continue its duration for 1 round and increase its radius by another 20 feet.