I am working on a dungeon adventure set for my players in the City of Greyhawk this summer.

As we all know, the adventure can take any direction or completely derail, but at least for now, I am creating drawings, maps, and write-ups for three locations.

The locations include the Black Lilly Inn, at the extreme South end of the wharf, in an aged and run-down area called Downbank, and the old Hill House ruin, located in the northeast corner of my map on the opposite side of the river from the city.

The Black Lilly is a location tied to one of two rival Guilds of Assassins I created for my campaign.  The guild involved with the inn is simply called The Brotherhood, which is a Lawfully aligned organization that receives contracts from a variety of powerful sources and offers these to a stable of approved independent freelancers.  The Brotherhood is a quasi-religious organization with centuries of rules that govern how freelancers are approved and how their professional behavior must be conducted both toward the public and toward one another.  The Brotherhood is inspired by fictional portrayals of groups like the Knights Templar.  Members of this guild are Lawful or Neutral in alignment because of the strict rules and traditions they must follow.

The rival guild to The Brotherhood is a highly secretive, radical religious cult called The Cult of Screams Cut Short.  The Cult worships an evil power whose details and name are kept a closely guarded secret.  The Cult is based on the strangler cult from the Black Company book series.  Screams Cut Short members can be of any alignment so long as they are evil and their membership in the cult is accepted by the dark power that guides them.

The Hill House is an isolated ruin that has stood abandoned for more than a century.  It is known to be a dangerous location, perhaps even haunted.  It has a certain reputation.  Only a handful of adventurers have ever managed to return from the place.  Those who did return came back wealthy individuals, although at least half of those who survived were so emotionally scarred that they left adventuring for good.

The third location I hope to include in this adventure is reached through the tunnels found below the City of Greyhawk.  I have some ideas about a reclusive order of clerics called The Grey Men, who choose to dwell in the tunnels and sewers below a city as part of their order's religious vows.  The Grey Men use some of their clerical magic to clean the water running into the city sanitation system as it moves through standing tanks and large sections filled with regularly refilled filters made from charcoal before it is allowed to exit the drains and return to the river.  The Grey Men will heal a wound or cure a disease for the poor and outcasts of the city who are brought to them in need.  The Grey Men do much to keep plagues of disease out of the city overhead.  They don't usually charge for their aid but sometimes will require that a later service of some sort be performed at their request.  Both the Beggar's Guild, the Thieves Guild, and the Merchant's Guild donate regular amounts of gold and supplies to the Grey Men for their valuable work and keep them handy as allies.