The current edition of Dungeons & Dragons offers several different campaign settings for the dungeon master to use in the base books of the game. The Player's Handbook and the Dungeon Master's Guide offer guidelines for running games in the Dragonlance, Eberron, Greyhawk, and Forgotten Realms settings, though we weren't given a ton of information about the individual settings. The information just acted as a guideline to help players create their character and get started in the game.
It seems that we will be receiving a new campaign setting later this year, as Nathan Stewart (the Brand Director and Executive Producer of Dungeons & Dragons) has revealed to ComicBook.com that a familiar setting will be receiving a fifth edition upgrade by the end of the year.
Nathan Stewart has compared the presentation of the new setting to the Curse of Strahd campaign, which outlined a setting alongside an adventure. In Curse of Strahd's case, the game outlined the realm of Barovia and discussed the rules that the denizens of the various realms of Ravenloft have to follow.
This means that the setting will probably be part of a new campaign, which will be competing with the upcoming adventures that are set in Waterdeep, which are also be released at the end of the year.
This leaves us the question of what the setting will be? It will almost certainly not be Eberron, Krynn (Dragonlance), Oerth (Greyhawk), or Toril (Forgotten Realms) as they have featured prominently in the previously released source material. Ravenloft has already been the setting for Curse of Strahd, so it's likely not one of the other Demiplanes of Dread.
Dark Sun is a potential candidate, as it was one of the most popular campaign settings of Advanced Dungeons & Dragons and made a comeback during the fourth edition era of Dungeons & Dragons. The fact that it saw a fairly recent upgrade may act against the world of Athas, as those who are thirsty for fighting monsters in the desert, can still pick up the fourth edition version of the campaign setting.
One prominent candidate is the Spelljammer setting, which is one of the most unusual settings ever released for Dungeons & Dragons. Spelljammer combines magic and technology, as sorcery-powered ships are used to sail across the galaxy. The currently released Dungeons & Dragons books have included a few subtle references to Spelljammer creatures and items, so this might be the most likely candidate for the new setting.
Planescape is another potential candidate, as it opens up the game to potential crossovers between the various settings. Planescape was the setting that showed the world between worlds and how reality was connected together. The Blood War would make an excellent backdrop for a campaign, so this is another strong candidate.
The least-likely candidates are probably Birthright, Council of Wyrms, and Ghostwalk, due to how unpopular they were when they were first released. They could still be considered outliers, considering that Nathan Stewart claimed that the new setting would please hardcore fans of the game.
The current Dungeons & Dragons adventures seem to be going out of their way to be experimental and shake up the dynamic of the game, with adventures like Curse of Strahd involving a random element when determining certain aspects of the story and Tomb of Annihilation requiring the players to explore an uncharted island for months before reaching their destination. The next campaign setting will likely follow this formula and be more than just a generic fantasy setting with a bunch of dragons and orcs to fight, as those are a dime a dozen nowadays.
Nathan Stewart has promised that we will learn more about the returning setting within the next month.
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