From the introduction:
This adventure can be can be easily customized to a party of any size or level, or run as a level 6 adventure for 5 players. It can work as a small side adventure in an existing campaign, as a standalone one-shot, or the start of a new adventure. Use the links to the tools in their relevant section to customize the adventure to your party.
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A vizier named Cecily Crawford has usurped the throne, using a cult of Vecna to consolidate her power and silence opponents. Now she seeks the Hand of Vecna and has started hiring adventurers to find it, promising vast rewards in return. This has made competition especially heated between adventuring groups that want to claim the reward for themselves, and one group seeks the hand to resurrect their lost loved member, no matter the consequences. The hand is rumored to be found in an ancient tomb along the river in the Lantan Hills.