Nightmare fuel, to be sure.
(More art to come.)
Picture if you will, a spider roughly the size of a horse with a massive skull on its back and wings like a locust. It paralyzes its victims with poison and cocoons them in a husk for later consumption in its lair. This carnivorous magical apex predator is a truly terrifying sight to behold. Worse yet, these arachnid beasts serve as consorts to the Spider Dragon.
Flying Skull Spider, Giant: Init +2; Atk bite +6 melee (1d8 plus poison)
or web (special); AC 14; HD 3d8; MV 30’ (climb any surface) or Fly 30′; Act 1d20; SP poison (DC 20 Fort save or lose an extra 3d4+4 hit points and 4 Strength temporarily; success results in loss of additional 1d4 hit points only), Web 1x/day (10’ range, DC 14 Ref save or –2 penalty on all actions until freed), stealthy (+10 to attempts to move silently); SV Fort +2, Ref +1, Will -1; AL C.
This creature is the unnatural fusion of demonic magic with an innocent forest arachnid. Afterward, nature took its course and a large clutch of baby monsters was born. Then they grew.