Alright, here's the first draft of my campaign document for Mu. It's based on the Sorcerer supplemt "Dictionary of Mu" -- I've altered it for d20, and tweaked a number of other elements to my liking.
And on the pedestal these words appear:
"My name is Ozymandias, king of kings:
Look on my works, ye mighty, and despair!"
Nothing beside remains: round the decay
Of that colossal wreck, boundless and bare,
The lone and level sands stretch far away.
-Ozymandias, Percy Shelley
The world of Mord is dying
Countless eons ago, Mord was a place of great beauty, a green jewel shining among the stars, but the slow passage of time has taken its toll. Forests and fields have been swallowed by the ever-expanding red desert, and the great ocean has been reduced to to a few meager brineflats. The works of the Old Ones -- mighty pyramids capable of sailing the void, metal stamped in the likeness of mind, hieroglyphs written in the strange language of Maths -- lie forgotten beneath the red sands, waiting for storms or arcane knowledge to bring them to light.
In dark Lemuria, the Witch-King sits atop his throne, gathering practitioners of dark and loathsome arts while the noble houses squabble over the scraps of power at his feet. His sorcerous followers make pacts with forces from forgotten epochs, and winged shapes wearing the faces of men darken the skies of Lemuria. It is whispered in the streets of his capital that the Witch-King has acquired a demon in the shape of a sword, a creature capable of consuming history itself...
To the east, the fanatical legions of Hy-Brasil are joined daily by new believers, eager to prove their worth to their Damsel Messiah so that they may be one of the 144,000 who join her when she ascends and leaves the wastes of Mord behind forever.
In the west, citizens of the decadent city-state of Atlantis sit idly in their crystal domes, unconcerned with the growing armies of Lemuria and Hy-Brasil. Under the domes, few surviving masters of enigmatic tradition of "psience" use their strange powers to grow powerful crystal weapons, strange alien beasts, and -- according to some -- even human life itself...
In times such as these, heroes are sorely needed -- will you restore Mord, or abandon it to its fate?
Mord is part of a jealous family of gods
Chief among the gods is Sar, he of the unblinking yellow eye. Sar is prayed to after sins -- not for forgiveness, as Sar has none, but to make the punishment swift and soon.
The Ringed Lord is a god of safety and family, symbolized by concentric circles drawn in the sand that represent the keep of stone rainbows that ward him and his family from harm.
Urd is the divine mother, the source of all life. It is said that when Mord dies, those who possess the means will travel to her gardens and rest forevermore.
Merkune is a god of greedy merchants, a lonely hermit guarding his endless silver mines and deep watering holes.
Venu is the goddess of love and beauty, but she has no sons or daughters, and it is said that her kiss is poison.
Few worship grim Mord directly anymore -- and those that do are an ill lot, for the god hates the parasites who live upon his world and desires nothing more than to be free of them.
There are others in the pantheon, but their temples are small and few.