The rider pried open yet another chest. This time, however, it wasn't gold or potions. It was several cases of scrolls. He opened one case, and brought out a particularly large piece of parchment. It muttered something about the 'Dark Ones', bla bla, bla bla. Apparently, kings and dragons of old merged blood to fight against these 'Darklings'. Wait. Was this why the queen transformed into a dragon? He read on. Apparently, the cure was in a special potion. Even the most experienced wizards could only contain it temporarily. The ultimate cure to this was the potion itself. He ruffled through the scrolls and books and pulled out a lengthy tome. He flipped it open onto a random page and saw that it was a journal of an apparently powerful archmage.
"I could not keep the potion for long. Bandits attacked me, beasts of the night tried to maul me. I stopped in the nearest farm I could find. It belonged to Baron Whatshisname... I forgot. Anyways, the farmer introduced himself as Moray Blackhilt..."
Dad?
"...a kind and honest worker. I told him to bury my potion in an untainted patch of land, fence it off, do whatever it takes to prevent people from getting it."
The rider briefly remembered a small fenced-off part of the farm that he was not allowed to go ANYWHERE near. It was all starting to fit together. But wait. This information... that that very worker was his father... if he sold it to the queen he could gain hundreds, thousands, millions of gold coins! He struggled to contain his excitement, and proceeded to ransack the rest of the room.