Praise of Yog-Sothoth

Stealth

+37 (legendary) to recognize the symbols as a magical trap

Disable

DC 47 Occultism (master) or DC 49 Religion (master) three times in a row to successfully speak aloud the esoteric phrases as they appear (this causes the trap to deactivate for 1 hour, although the phrases continue to appear during this time), or dispel magic (9th level, counteract DC 38).

Reactive Charge [Reaction] (arcane, evocation) Trigger A creature spends more than 1 round in the room without speaking aloud the phrases appearing in the alcove.

Routine

(1 action) The trap fills the entirety of area B4 with additional blasts of cold. All creatures in area B4 take 12d6 cold damage (DC 41 basic Fortitude save, plus immobilized for 1 minute on a critical failure).