(warning, Incoming wall of text!)
Alrightly then, Druce knows that Kryshtak was a mighty wizard who took over the Kingdom of Jaldrin, then went on a campaign of conquest until the whole of the highlands was under his control. Ruling from his tower-keep located not far from this town, he kept everyone taxed into almost starvation, while his bullyboys and enforcers made sure anyone who even thought of rebelling died a gruesome death. As well, the surrounding kingdoms saw his military might and arcane power, and sent him hefty tributes of rare gems, gold, and priceless works of art in hopes to keep him from invading and conquering them as well. As such, he acquired a vast amount of wealth that he hid away, that remains hidden well after the Grand Alliance of Kingdoms finally put an end to his reign a couple hundred years ago....
Darvi, your character knows much of the same thing, but you also know that the historian Ugar The Blind chronicled that Kryshtak was actually the illegitimate son of the king of Jaldrin and a passing dancer(though later histories brand her a demon in disguise). Raised in the palace, he had no real place there, being not in the line of succession, and in desperation turned to the arcane arts to find his purpose. Tainted by the bitterness and jealousy of seeing men he thought beneath him being given great fame and glory, his arts turned blacker and blacker, until rumors swirled of necromancy and deamon worship. When the king had him summoned to answer these foul rumors, he saw his chance, and used his arts to slay his own father and usurp the throne. It is said his magical might stemmed from a pact he made with one of the lords of Hell in exchange for a promise of his soul and to conquer all the known realm in the demon's name.....
Rolepgeek, your char doesn't know much about the man himself so much as about the various legends surrounding his keep, and the catacombs full of treasure specifically. It is said that after he ursurped the throne for himself, to demonstrate his power he called forth lightning storms and fire from the sky to raze the palace to the ground, sending his very image into the sky declaring that all who opposed him would meet the same fate, and all who joined him would be rich beyond their wildest dreams. The next day, the tower sprang up, as if it had grown like a tree overnight. I appeared as if it was carved from the blackest ebony, and the stones were said to be harder than diamond. The outer walls surrounding the tower were patrolled by horrifying abominations of nature, and at night demons roamed the grounds. All who were taken into the tower itself were never heard from again, except from time to time when their twisted bodies were hung from the walls as a reminder of the fate of those who dared oppose him.
After several years, it is said the treasure rooms of the tower actually ran out of space to store all of the tribute Kryshtak was receiving, so he commisioned several architects to design and build a vast vault underneath his tower, connected by several networks of tunnels and catacombs lined with fiendish and clever traps, as well as guarded by unholy spirits and summoned demons. Naturally, when the catacombs were completed, Kryshtak had all involved executed on trumped up charged of treason, keeping the location of the only entrance to the tunnels to himself. Many have searched for that entrance, looking for the wealth of a hundred kingdoms....