I'm thinking the Celestial Nadir, or an 5e update to Desert of Desolution, or a portal hopping adventure across multiple setting to get parts for a McGriffin, I forget what it is called (like one part is in FR, another part is in Greyhawk, another part is in Eberron, another part is in Ravnica, another Dragonlance, another in Mystara, Athas.