Most of the official campaign settings for Dungeons & Dragons cleave to classic archetypes of Western fantasy; the worlds of Greyhawk, Dragonlance, and the Forgotten Realms are full of forests, mountains, and farmlands, where human, elves, dwarves, and other humanoid races go on magical adventures. The following D&D campaign settings, in contrast, delve into strange territory, immersing tabletop gamers in weird worlds with science-fiction elements, harsh desert environments, and existential philosophy.
Classic stories like The Lord Of The Rings and Conan The Barbarian established the look and feel of Western fantasy. However, it was the success of Dungeons & Dragons, the first fantasy roleplaying game, that popularized the archetypal Western fantasy world seen in media like The Elder Scrolls and Dragon Quest - a medieval setting with elves who live in forests, dwarves who mine mountains, wizards who study in towers, and dark lords who must be defeated by heroic adventurers.
Three out of four of the D&D campaign settings listed below were devised by D&D writers in the late 1980s, during the era of Advanced Dungeons & Dragons Second Edition. Some of these settings were updated for later editions of D&D, while others were simply incorporated into the broader setting of the Dungeons & Dragons multiverse, becoming odd locations adventuring parties could visit by traveling through the Astral Planes. What makes these campaign settings special is how they expanded the possible range of stories D&D could tell, making the world's first fantasy roleplaying game more than just a "standard fantasy" simulator.
Strange D&D Settings: Planescape
The core locale of the Planescape: Torment computer RPG.
Strange D&D Settings: Eberron
Most tabletop fantasy settings tend to be stuck in a sort of technological stasis, where centuries can without significant advancement or, for that matter, even the invention of any new spells. Not so for Eberron, a D&D fantasy setting created by Keith Baker, famous for popularizing the "Dungeon Punk" subgenre of fantasy, where magic is used to create an industrial society. In most Eberron RPG campaigns, player characters start out as veterans of a global conflict known as the Last War, now using their skills at fighting, stealth, spell-craft, and diplomacy to engage in mercenary work and go on adventures. The Eberron setting introduced the Artificer class to D&D - a magician who infuses tools and potions with magic - and the Warforged, a race of military machines searching for a new purpose after the war they were built for ended.
Strange D&D Settings: Dark Sun
Inspired by planetary romance sagas and post-apocalyptic yarns, the world of Athas, centerpiece of the desert landscape straight out of Dune, dominated by imperious city-states and cruel, immortal sorcerer-kings who control the remaining water reserves. The wilderness of Athas is filled with scorched plains of sand, predator insect packs, carnivorous plants, and Halfling cannibals. A key feature of the Dark Sun setting, besides stories about making harsh choices to survive, is its emphasis on Psionic powers as a substitute for Arcane magic.
Strange D&D Settings: Spelljammer
The titular "Spelljammers" of D&D's Spelljammer setting are basically magical spaceships, flying through a cosmos with planets surrounded by crystal spheres (a concept directly inspired by the "Celestial Sphere" theories popularized by Plato and Aristotle). Through Spelljammers, adventuring parties can essentially travel between different D&D campaign settings, fending off magical space pirates and hostile cosmic lifeforms all the whole. Wizards Of The Coast has not yet updated the Spelljammer setting for 5e, but ideas from it have seeped into other official Dungeons & Dragons works over the years: For instance, the mind-flayer controlled Nautiloid ship seen in the opening cinematic of Baldur's Gate 3 is a Spelljammer in all but name.