The Vespers of the Silent Ferryman - AI-generated fantasy Puzzle

The Vespers of the Silent Ferryman

The air in this windowless chamber is thick with the cloying scent of myrrh and ancient, cold wax. Five obsidian-black candles are spaced evenly around a massive basalt slab, their flames flickering with an unnatural, blue-tinted light despite the lack of a breeze. Shadows seem to stretch toward the center of the room rather than away from the flames, pooling like ink around the base of the altar. Deeply carved grooves in the floor connect the candle bases to the central slab, creating a circuit that hums with a faint, low-frequency vibration felt in the marrow of one's bones.