The hidden subterranean chamber beneath the Oracle's Hall. A dark, cramped space with a low, arched stone ceiling dripping with moisture. In the center, a priest in dark robes performs a ritual, generating an eerie, otherworldly green or blue light that seems to seep upwards through the stone. The scene is lit by a few flickering torches, casting deep, dancing shadows. Claustrophobic, ritualistic, occult atmosphere, hyper-detailed, volumetric smoke, style of H.R. Giger mixed with ancient architecture.