Some have worried bringing Sigil (also known as the City of Doors) to Dungeons & Dragons Fifth Edition could be a big mistake, but the upcoming three book collection, Planescape: Adventures In the Multiverse, is a gateway to infinite possibility dungeon masters and players alike will want to explore. While there are definitely characters perfectly content to stick to Prime Material Plane and play the hero to their fellow planar locals, there are others who were born to brave the unknown. With the potential for rich story, the former incarnations of this setting had a heavy reliance on the alignment system, which is not nearly as predominant in 5e and could be an interesting avenue to explore for newer players.
Source：https://www.cbr.com/dnd-5e-planescape-adventures-in-the-multiverse/
