Both Hurcula and Yaroslav, unbeknownst to the party, desired a codex that lay beneath the Castle. THe codex held much power in the way of magic, and the monks had sworn to protect it. It was an evil book, its pages made from slivers of bone upon which the letters of the writing was carved. Its cover was said to have been bound in the flesh of children.
This foul work that the monks had sworn to hide from the world, being unable to destroy it, was created by an ancient and evil sorceror named Lulach. It was this codex that had driven an unsuspecting monk insane. It was this that had called to the unprotected monk, staining his soul, and reaching into his very dreams....
the Key to the book was an amulet used to lock it by the Holy Seers. It was their order charged to protect it. THe book had some kind of sentience of its own. It did not like being locked. It had acted. Tempting the young monk and seducing him. He had died screaming out spell out of spell from the book that briefly took over his body when he touched it...an ice demon was just one of the creatures summoned. Dead turned undead, and many other horrors were unleashed.
The head monk had used his powers to seal the deepest caves, burrows, ans catacombs of the monastary...trapping the evils within. One monk fled with the medalliion. He had been a younger alcolyte.
Yaroslav had sent Malatan to get the medallion. His plan had been to use the man to get to the book. his own agent had been with him. Only that agent had disappeared....
Hercula too needed that amulet, it was the only garantee of safety to get to the codex. If Yaroslav was not spending so much power combatting Herucla and her powers retreiving the book would be easier...