Carstigle Wormhand is dead.
The powerful mage was said to have kept an apprentice and yet his lair remains abandoned, the many treasures and wonders within left for the taking.
There are defenders of course—creatures left to protect his legacy—but they are unique, laying in a cunning and clever trap that has claimed every intruder so far.
What makes you think you'll fare any better?
Book of Exalted Darkness: Reduci Castle is a locale and coterie of NPCs best suited for adventurers between 8th–10th level. Within you'll find statistics for 10 monsters and castle denizens, the Vile school of magic (over two dozen new and truly evil spells), as well as rules on expanded madness (more options for the short-term, long-term, and indefinite varieties).
If you aren't already in the know, check out the Book of Exalted Darkness campaign setting book, and should a quick skim fail to convince you to try out the free Killing the Golden Twins adventure then take a gander at the (also free) Evil Primer and then take the plunge into evil adventuring!