Wizards of the Coast's upcoming D&D book, Quest from the Infinite Staircase, remixes six adventures from the Advanced Dungeons & Dragons 1st edition era. The latter is also available in an abridged version called "The Descent into the Lost Caves of Tsokant," which is currently available for free on request at DND Beyond.

First published in 1982, "The Lost Cave of Tsoikant" began six years earlier as a tournament module run by D&D co-creator Gary Geigax. It was a competitive one-shot designed to kill the characters that players brought to the tournament game, and was unforgiving even in its modified and published form. A nice record of this is the comic-style walk-through map of this module by Jason Thompson. In this map, one of the party members is crushed to death by a rock before reaching the dungeon.

Tsojcanth was both just a dungeon crawl, but was notable for the plethora of new monsters added to D&D, such as water monsters, Beheir, Marid, Delo, and various demon princes like Graz'zt and Baphomet. If you're interested in this topic, here's more on the origins of some of D&D's stranger creatures, especially those encountered in Baldur's Gate 3.

Quest from the Infinite Staircase transforms these old adventures into a new campaign. In this new adventure anthology, the player character is recruited by a genie named Nafas, who uses his heroes to grant wishes in various worlds. The anthology is designed so that each scenario can be run individually or as a linked campaign for characters from level 1 to level 13, and will be released on July 16.