Describe the terrifying yet fascinating atmosphere of the underworld

Describe the terrifying yet fascinating atmosphere of the underworld., where pointed buildings lit by firelight are arranged around a red river and burning earth, From behind an old man with long white hair, with a black winged dragon in the middle of a full moon background, and mumford tom bagshaw, and mumford tom bagshaw, dark surreal art, detailed 4k horror artwork, beksinski and dan mumford, el bosco and and mumford, dark surreal art, surreal horror art, surreal dark fantasy, unpleasant fantasy illustration, anton fadeev and dan mumford