Tide Lock of the Drowned Vault

The vault door looms six feet across, its face carved with nine sea-worn glyphs around a central plate like a ship's wheel sunk into stone. Thin veins of blue-green glass catch the light like submerged lanterns, and a cold brine smell leaks from the seams. The moment anyone nears, the plaque hums softly and a whisper of surf rolls through the chamber, while the wrong glyph hisses a burst of salt mist from the lower vents, as if the door itself were exhaling.