Echoing Crystal Spires
A cluster of translucent, jagged crystals growing from the cave floor and ceiling. These stones are attuned to vibration and begin to pulse with a low, bone-shaking hum when creatures move nearby, eventually creating a cacophony that can shatter glass and daze the mind.
Echoing Crystal Spires
Defenses
Detection
“Clusters of pale blue quartz grow in geometric patterns along the walls. The air around them seems to shimmer with a heat-haze effect, though the cave remains cold.”
Standard Engagement
A creature enters the area or makes a sound louder than a whisper.
The hazard takes 2 actions on its turn. (Action 1) Harmonic Pulse: The crystals emit a thrumming wave of sound. Every creature within 15 feet must attempt a DC 14 Fortitude save. On a failure, the creature takes 1d4 sonic damage and is deafened for 1 round. On a critical failure, the creature is also sickened 1 from the nausea caused by the vibration. (Action 2) Escalating Frequency: The hazard increases its pitch. The DC for the Harmonic Pulse increases by 1 for the next round (maximum DC 18).
The crystals go dormant after 1 minute of silence and lack of movement in their vicinity.
If a creature inside the area uses an action with the Auditory or Sonic trait, the hazard immediately uses a Harmonic Pulse as a reaction against that creature.
The crystals are part of the cave wall. While they can be destroyed, their Hardness applies to all attacks. If the hazard is reduced to 0 HP, it shatters loudly, dealing 1d6 piercing damage to all adjacent creatures.
Turn Echoing Crystal Spires into a sheet
A high-res, share-ready sheet you can post or print.