Dios and Vorbis make look alike superficially--but in fact they are quite different. Poor old Dios has none of the intellectual power of Vorbis. And he has convinced himself that what he is doing is for the good of the country. The fact that he has become more or less immortal is, in his mind, just a temporary state until things are in better shape. Thus, he insists on repeating things over & over because that's the way it's always been done. He will neatly dispose of or frustrate any attempt at change. He has been happily "creating" gods for centuries--to fill a particular need in his society. When they actually appear, he is totally at a loss and has no idea what to do with them or how to deal with the imminent destruction of the country because of the newest pyramid.
Vorbis, on the other hand, is probably the most thoroughly amoral and evil character Pratchett has created. He is amoral because he believes in nothing--he has no concept of morality. He has become a control freak, a megalomaniac far removed from Dios. Two incidents make clear Pratchett's use of him. In the beginning of the book, Vorbis turns the tortoise (who happens to be Om) on its back and props it there--apparently for no reason but only because he can. He doesn't even stay to see how long it takes for the creature to die. He has no idea that he is dealing with (albeit at this point) a small god. He causes suffering and possible death because he can and because he likes the feeling of power it gives him. The other incident(s) have to do with the death of Vorbis and Brutha. When Vorbis finds himself confronting DEATH - he becomes paralyzed because when he looks within himself, he finds an empty space. When Brutha dies, he finds DEATH and Vorbis. Brutha is a bit disconcerted to think that Vorbis has been so long trapped in the desert. DEATH describes Vorbis: "HE WAS A MURDERER. ... AND A CREATOR OF MURDERS. A TORTURER. WITHOUT PASSION. CRUEL. CALLOUS. COMPASSIONLESS.
That characterization is quite different from that of Dios. And their eventual fates show Pratchett's wry humor. Dios "dies" and starts the whole cycle over again. Vorbis still cannot cross the desert without Brutha.


