Rat King’s Sewer is a dungeon crawl mystery set in the sewers beneath the city of Eastgate in the Borderlands Provinces. Found on the eastern side of the continent of Akados in the world of Frog God Games’ Lost Lands, Eastgate is a bustling city at the mouth of the Amrin River. As most of the adventure takes place in the sewers, and nearly all of it in an urban setting, wilderness-orientated characters might find themselves at a disadvantage. Then again, the sewers are a maze filled with all manner of deadly creatures, so the ability to talk to cockroaches might just prove useful.
Rat King’s Sewer is available in 5e or OSR-compatible versions. The 5e version is suitable for late Tier 1 and early Tier 2 play. The OSR version is suitable for characters of 4th to 6th levels.
While on her way home from the opera, Lady Volcula Soninius was attacked by thieves. Her bodyguards were quickly dispatched, but the aging noblewoman was more than capable of putting up a fight. During the battle, one of the thieves grabbed her necklace and broke it, causing a cascade of jewels to fall into the gutter. After the brigands were driven off, Lady Volcula attempted to retrieve her lost jewels, but the largest had fallen into the sewers. She watched in horror as a vile rat scurried out, gobbled it up, and disappeared.
That was two days ago. In that time, dozens have ventured into the sewers beneath the city hunting for the rat. Thousands more have taken to the gutters, the alleys, and the slums of the city hunting for the rat with a jewel in its stomach. Bands of searchers turned on each other, and the city looks to be spiraling toward madness. Yet no one has found the jewel.