Well, if you want inspiration I found this site:

[url=http://waynebarlowe.wordpress.com/artwork/hell/]Go to hell[/url]

And holy shit, I found a pretty badass demon lord for the Spine of Iron:

[img=http://fc01.deviantart.net/fs71/f/2012/210/7/3/undead_dungeon_master_by_vegasmike-d593nv6.jpg]

Wondering if I should go with the spine of Iron or go with a hypothetical endless building realm that is akin to MC Esher or a aquatic realm where everything is underwater. Maybe a realm where everyone must live in a giant, vast tree that is in the middle of a endless wasteland patrolled by giant birds that look humiliatingly like sparrows.

Or perhaps there can be a candy realm where candy grows as trees and giant, sentient blobs of dough engulf/devour little children in the forests made of lollipops. Candy land is what this RP needs. The Demon Lord can be willy wonka.