While reading the excellent Del Rey Kull collection, I came across this passage in the story The Cat and the Skull (page 114):

Kull tore the veil away with one motion and recoiled with a gasp. Delcardes screamed and her knees gave way; the councillors pressed backward, faces white and the guard released their grasp and shrank horror-struck away.
The face of the man was a bare white skull, in whose eye sockets flamed livid fire!
“Thulsa Doom!”
“Aye, I guessed as much!” exclaimed Ka-nu.
“Aye, Thulsa Doom, fools!” the voice echoed cavernously and hollowly. “The greatest of all wizards and your eternal foe, Kull of Atlantis. You have won this tilt but, beware, there shall be others.”

Totally Skeletor. The Del Rey edition is filled with art by Justin Sweet (like, one every few pages). Here is the one illustrating the scene above:

Somewhat related, these are the reading materials I took along for vacation reading (not including the three lifetimes worth of digital material I have on my tablet). Still reading Warhammer too, but I decided to leave that massive book at home.

In case that picture is not clear, those are WMLP No. 1, Coercion, Capital, and European States: AD 990 – 1992, the old D&D Gazetteer GAZ3 The Principalities of Glantri, Changeling: The Dreaming (for some faerie inspiration), and the aforementioned Kull collection.