The Bloody Vault of Belphegor

Local legend has it that a hidden cult has bound a demon and is forcing it to provide an inexhaustible list of inventions, discoveries, and secrets.

As the adventurers arrive, a series of bloodcurdling screams are heard... and the underground lair of the cult is empty except for an unbelievable amount of blood and gore.

What is going on? Are the tales true? And what of the supposed wealth the cult acquired from its demonic tutelage?

A map for use with Adventure Kit RPG (or a game of your choice).