Stygian

synonyms

Acheronian

Acherontic

Cimmerian

Lethean

Plutonian

Plutonic

Tartarean

chthonian

chthonic

clouded

cloudy

dark and gloomy

devilish

funereal

gloomful

glooming

gloomy

hellborn

hellish

ill-lighted

ill-lit

infernal

lowering

overcast

pandemoniac

pandemonic

purgatorial

somber

sombrous

stormy

sulfurous