Your drumming skills can break solid rock.
Cost: Feat or 5th-level bard spell known.
Effect: Like a singer shattering a wine glass with a perfect note, your music cracks stone, shivering solid rock until it snaps. When you complete the performance, you create a tremor identical to an earthquake spell.
For each round you continue to expend bardic performance rounds, the area experiences a round-long aftershock, which has the following effects.
Cliffs: More cliffs crumble, creating a landslide that travels half as far horizontally as it falls vertically. Any creature in the path takes 4d6 points of bludgeoning damage (Reflex DC 5 half) and is pinned beneath the rubble.
Open Ground: Each creature standing in the area must make a DC 5 Reflex save or fall down. Fissures open in the earth, and every creature on the ground has a 25% chance of falling into one (Reflex DC 10 to avoid a fissure). The fissures are 20 feet deep, and these fissures remain open at the end of the quake.
Pinned Beneath Rubble: Any creature pinned by the effects of the aftershock takes 1d3 points of nonlethal damage per minute while pinned. If a pinned character falls unconscious, she must make a DC 5 Constitution check or take 1d3 points of lethal damage each minute thereafter until freed or dead.
Rivers, Lakes, or Marshes: The area drained away by the earthquake remains drained for the duration of the aftershock.
Spellcasting: The concentration DC to cast during an aftershock is 15 + the spell’s level.
Structure: Any structure standing on open ground takes 50 points of damage. A collapsing structure deals 4d6 points of bludgeoning damage to creatures inside it (Reflex DC 5 half), and the creatures inside are pinned beneath the rubble.
Use: 10 rounds of bardic performance, +1 round for each round of aftershocks.
Action: 10 full rounds.