Beyond the Black Door, D&D 5E and OSR High-level Adventure

The shifting sands of the desert have unearthed ruins buried since time immemorial. The legends of the dune walkers have told of the buried city of Al' Akra, the City of Winds, a place of alien architecture, implacable guardians, arbitrary winds of great power, and an impenetrable black door deep underground. It is only a matter of time before the sandstorms return, potentially burying the city once again. Race against time and against factions whose goals run contrary to that of humankind to discover the secrets of Al' Akra and decide whether to venture beyond the black door.