Hm. If there's going to be a seperate dark chapter or book or section or whatever, I may have something to contribute. Basically, a really vile form of magic that works by destroying innocence, and the worse the destruction and the purer the original innocence, the more powerful.
I like my villains to be REALLY vile, that way when the heroes stop it, they're REALLY heroes. It's easy to define yourself by who your enemies are, and as such, the worse the enemy, the better the hero.
The PrC would work by gaining caster levels twice as fast as a Wizard, but losing -all- free spells per day. Spells per day would only be earned by doing horrible horrible things, and that goes for all that player's magic... having a single level of this class would make it impossible to cast spells even known before without doing something wicked to the innocent. A true exchange of power for evil.
