B4: The Lost City
The Lost City is an adventure module for Dungeons & Dragons BECMI, released in 1982. It centers around the Lost City of Cynidicea, and is in general one of the more Sword & Sorcery-themed adventures based in the setting.
Getting lost in the desert thanks to a sandstorm, the party stumbles across a massive ruined pyramid. Seeking shelter inside, they discover a decaying underground city, Cynidicea, still inhabited by a people who have succumbed to decadence and degeneration; they live in a perpetual drug-fueled haze, blitzed out of their mind on narcotic fungi they wander around in drunken revelry, clad in ornate masks and elaborate costumes. The Cynidiceans were led to this state of ruin by a terrible god-monster, Zargon, whose cult presides over the eternal debauch and sporadically selects victims to sacrifice them to Zargon's hunger. Three different sects of Cynidiceans still maintain their sanity and oppose the cult of Zargon... but each is the remnant of the cult of one of the three former gods of Cynidicea; the Brotherhood of Gorm worships the God of Justice, War and Storms; the Magi of Usamigaras worship the God of Healing, Messengers, Thieves and Magic; and the Warrior-Maidens of Madarua worship the Goddess of Birth, Death and Seasons. As such, they waste their strength and time by squabbling with each other over religion rather than uniting to face the common foe.
It's up to the party whether they try and free Cynidecia from its monstrous overlord... or just survive long enough to get out of this crazy place and leave its mad denizens to rot.
Although it's not focused on in any of the sources, almost all versions of the Lost City have mentioned that, mechanically, Cynidiceans use the same mechanics for their edition as humans, save for also having the Low-Light Vision and Light Sensitivity traits, much like a playable Goblin. Even the 4e version from the Dungeon Survival Handbook presents a Cynidicean escapee background, although without the mechanical impact of earlier editions. The obvious inference is that you could play a Cynidicean PC if you really want to.
The Lost City was written by Tom Moldvay and illustrated by Jim Holloway. It was published by TSR in 1982 as a 32-page book with an outer folder; the first printing was 3-hole punched. This module includes a cover folder with maps and a descriptive booklet with ready-made adventurers for the Dungeons & Dragons Basic Game. It also includes enough information to continue the adventure beyond level 3, using the Dungeons & Dragons Expert Game rules. This adventure was partially reprinted in the supermodule compilation B1-9 In Search of Adventure (1985), which included only the upper pyramid and was set in the Mystara campaign setting.
The module was the inspiration for a 3rd edition D&D adventure, "Masque of Dreams," which was printed in Dungeon #142. The adventure was written by B. Matthew Conklin and illustrated by Michael William Kaluta.
Zargon and the Cynidiceans received a re-interpretation in the 3.5 edition product, Elder Evils, which places the temple in the default, Greyhawk-like setting, though the book also includes short sections on how to adjust it for Eberron or Faerun.
A reprint and 5e conversion for this module was released in 2020 by Goodman Games under the title "Original Adventures Reincarnated #4 The Lost City."