Conjurer Thalerian must be stopped.
He immediately sought out my father's private study when he arrived and he has not yet emerged. I worry that he may have found a very dangerous item.
It is called the Astromancer's Keystone. It is used to manipulate the stronghold's defenses.
Such magic was meant to protect the Moon Guard- used for any other purpose and it becomes unspeakably destructive.
Retrieve the Keystone. Slay Conjurer Thalerian to get it, if you must.