I've read a few times in various threads that some people consider Skeletor to be dead.
Before the addition of Keldor, I always considered Skeletor to be a demon with a skull like face. I felt the floating head look was just an artist's shortcut rather than proof that he was one of the walking dead.
In MOTUC, I took Skeletor to be a medieval Two-Face who was "healed" by being merged with Demo-Man rather than a stay in the burn ward.
Do You Consider Skeletor To Be Dead?