New monster, I like.

[Null]

arch shogoliches smash like ghasts >_> deadly

[Fredd]

Was reading in one of the Sword of Truth books, that the undead draw their energy from the Negative Material Plane, opposed as to the Material plane. There is actually 3 categories for undead, 1 is the undead that have physical bodies, who keep their mental processes, but draw their energy from that plane.(Vampires, Lichs.) Next is undead which have physical bodies, but are controlled by evil spirits,(Mummys, ghouls,zombies). Finally there are the ones that are exist on this plane, which have a non corporal form(Wraiths, ghosts,Reapers, etc).
Salky, I have bad news, all a lich is ia a uber mummy, which still has control over its own actions.
Demons that are here are just a physical form they have to take while on this plane. When you destroy one here, you don't actually kill it, cause it still exists on its home plane. I don't think you would want to go to a map where a demon actually lived, because there power here is just a little bit compared to the power they would have, on their home plane.
You could explain Hades away as a halfway point between the abyss, and the prime material plane.<<<Still thinks the Arch Shoggy was a experiment gone bad by a crazed mage*Hides from Binyamin*

[Linda]

A lich is a wizard who decided not to die by constructing a phylactery and trapping his soul within it. The body rots, but the bones and the magical energy remain. The skeleton used by a lich is the same that it owned in life, not that of some other creature.

[Linda]

The point is that a lich's body [i:6c80d]isn't[/i:6c80d] destroyed; the flesh rots away, but the bones remain.

[Fredd]

<<What Linda said. The energy it draws from the Negative plane slows down the degeneration of its physical form. So thats why it drains xp, to keep itself going.