"The blood of the demons quickened as their master rose over the battlefield. The blood of the angels also quickened: here was the chance to finally end the war started millennia ago."
Basically, he's Mr. Big Bad Himself.
"Think of every fairy-tale villainess you've ever heard of. Think of those wicked witches, the evil queens, the mad enchantresses. Think of the alluring sirens, the hungry ogresses, the savage she-beasts. Think of them and remember that somewhere, sometime, they've all been real.
Mab gave them lessons."
—Harry Dresden, Small Favor
"It was Voldemort, Harry thought, staring up at the canopy of his bed in the darkness, it all came back to Voldemort. He was the one who had torn those families apart, who had ruined all those lives."
"For years past I have continually been conscious of some power behind the malefactor, some deep organising power which forever stands in the way of the law, and throws its shield over the wrong-doer. Again and again in cases of the most varying sorts--forgery cases, robberies, murders--I have felt the presence of this force, and I have deduced its action in many of those undiscovered crimes in which I have not been personally consulted. For years I have endeavoured to break through the veil which shrouded it, and at last the time came when I seized my thread and followed it, until it led me, after a thousand cunning windings, to ex-Professor Moriarty of mathematical celebrity. He is the Napoleon of crime, Watson. He is the organiser of half that is evil and of nearly all that is undetected in this great city."—Sherlock Holmes, "The Final Problem"
"Sometimes life seems so complicated. Nothing is truly good or truly evil. Everything seems to be a shade of grey. And then you spend some time with a man like Dukat, and you realize that there is such a thing as truly evil."—Benjamin Sisko, Star Trek: Deep Space Nine ("Waltz")