Describe the terrifying yet fascinating atmosphere of the underworld

$Describe the terrifying yet fascinating atmosphere of the underworld., From behind an old man with long white hair, wear a blue shirt with a gold pilgrimage, In front of the terrible Demon king with the background of the terrible castle, surrounded by demons and ghosts, anton fadeev dan dan mumford, beksinski dan dan mumford, highly detailed fantasy art, dan mumford. concept art, inspired by Aleksi Briclot, hell view, and mumford and peter mohrbacher, fractal thunder and mumford, ( ( ( ( ( ( ( dan mumford)) ) ) )$