From the introduction:
This adventure is designed for 3 to 8 beginning 1st level or low-level characters. It may also be used as a solo adventure for 1 character of 3rd to 5th level. It is suggested that low level parties accompany the game's NPC to the manor. Higher level party's can explore the manor on their own.
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Twenty-three years ago Lord Drestyn retired from adventuring with a large sum of wealth. He used some of his funds to build a manor at a scenic and private location. It was completed in two years. To gain popularity, he began hosting expensive parties and dinners. He quickly won over the neighboring nobles with his generosity. The escorts (guards, drivers, etc.) accompanying the guests normally stayed in Ambroth, the nearby village. As a result, a few inns, taverns, and other shops sprang up in the village. Everyone was happy.