Tomb of the Rancid King

From publisher blurb:

A 5th Edition Mini-Dungeon for four to five characters of levels 7-9

This module’s lead-in best works in craggy terrain during a random encounter. After a few rounds, the ground begins to rumble and shift as a sinkhole opens, sending boulders and combatants tumbling thirty feet down into a cavernous chamber.

This is the lost tomb of Daruig Danan who was known by the moniker, “The Rancid King.” He was a reviled warlord who subjugated local provinces under tyrannical rule. After dying suddenly, his twin sons Gildan and Rhodig fought for throne and supremacy, plunging the region into civil war. The twins perished in combat; their bodies enshrined in the Rancid King’s tomb.