GM's Note: I was inspired by Dave Arneson's Blackmoor campaign in the late 70s. With Gary Gygax, Arneson created the original D&D rules and setting. You can read about Arneson's vision of The Temple and "Saint Stephen," though my version, while inspired by them, is very different indeed. You won't find a crashed spaceship or Lovecraft's Old Ones in my temple, but there are other powers and terrors at work.
The Temple has always been there, some say. Others say it has only been a few generations since Steven the Rock, a wandering hermit, went into the swamp at the confluence of the Sarnell and Westerling Rivers to meet his destiny.
Every subsequent ruler of the Temple, dedicated to the god Thoggu, has been called Steven The Rock, or "The Steven" since. The successor to the current Steven is a woman named Prana.
It's not a place to be taken lightly. No riverboat may pass without paying toll, which can be paid off by the crews doing forced labor on the docks, which require constant repairs. The entire city, save the rock on which the Temple and a few other buildings stand, rises out of the swampy confluence of the river on pilings. Wood is a major import, and carpentry a prized skill.
The Temple has excellent trading relations with Windamere, and the veneration of Markik and Orozan tolerated if not encouraged. The Khan is on rotten terms with Steven's people, ever since a Black Fleet vanished while trying to force their way through the river and take the Temple, in order to isolate Windamere. Only one survivor was reported to have come back to tell the Khan and his Barons of the disaster. Some Barons are on better terms, though their ships are not permitted through Windamere to reach the Temple.
Today, visitors of means often seek out The Darkened Room, run by a friend of the Temple named Jira. Aside from the usual fleshly and culinary pleasures, Jira offers dreams: smoking the powered root of the Swamp Lily, found only around the Temple, both addicts over time but also grants real visions, not merely pipe-dreams.
There are said to be creatures near and perhaps in the Temple that are hybrids of frogs and humans. No one knows their purpose or powers. The Temple apparently has them assist in mining jade and gold from the swamp, and the jewelry of the Temple is of stunning design, even prized by the Rindalar who are connoisseurs of beautiful ornaments.
Outside of the Temple, the cult has a few far-flung outposts, always near great marshes and swamps. Adept Mathias is the leader of the smaller temple in Thozanga, noted for its water-gardens.