Verbosh, softback supplement for Original and Basic Dungeons & Dragons, by Paul Nevins and Bill Faust
“Nestled along the banks of the river known as “The Great Source”, stands the might fortress City of Verbosh.
More than the usual dungeon adventure, this is a complete micro-campaign that will keep the players busy for days on end… if they survive. The two dungeons include the three-level sewers and dungeons beneath the city of Verbosh and the nine-level Schawang-Nau Tower.”
This is a third printing from 1981.