The rules and story elements in the D&D game are built around a set of core assumptions about the world. Here are some of the most important.
The World Is a Fantastic Place.
Magic works, servants of the gods wield divine power, and fire giants build strongholds in active volcanoes. The world might be based on reality, but it’s a blend of real-world physics, cultures, and history with a heavy dose of fantasy. For the game’s purposes, it doesn’t matter what historical paladins were like; it cares about what paladins are like in the fantasy world.
The World Is Ancient.
Empires rise and empires crumble, leaving few places that have not been touched by their grandeur. Ruin, time, and natural forces eventually claim all, leaving the D&D world rich with places of adventure and mystery. Ancient civilizations and their knowledge survive in legends, magic items, and the ruins they left behind, but chaos and darkness inevitably follow an empire’s collapse. Each new realm must carve a place out of the world rather than build on the efforts of past civilizations.
The World Is Mysterious.
Wild, uncontrolled regions abound and cover most of the world. Citystates of various races dot the darkness, bastions in the wilderness built amid the ruins of the past. Some of these settlements are “points of light” where adventurers can expect peaceful interaction with the inhabitants, but many more are dangerous. No one race lords over the world, and vast kingdoms are rare. People know the area they live in well, and they’ve heard stories of other places from merchants and travelers, but few know what lies beyond the mountains or in the depth of the great forest unless they’ve been there personally.
Monsters Are Everywhere.
Most monsters of the world are as natural as bears or horses are on Earth, and monsters inhabit civilized parts of the world and the wilderness alike. Griffon riders patrol the skies over dwarf cities, domesticated behemoths carry trade goods over long distances, a yuan-ti empire holds sway just a few hundred miles from a human kingdom, and a troop of ice archons from the Elemental Chaos might suddenly appear in the mountains near a major city.
Adventurers Are Exceptional.
Player characters are the pioneers, explorers, trailblazers, thrill seekers, and heroes of the D&D world. Although nonplayer characters might have a class and gain power, they do not necessarily advance as PCs do, and they exist for a different purpose. Not everyone in the world gains levels as PCs do. An NPC might be a veteran of numerous battles and still not become a 3rd-level fighter; an army of elves is made up of soldiers, not fighters.
The Civilized Races Band Together.
The character races in the Player’s Handbook all drew closer together during the time of the last great empire (which was human-dominated). That’s what makes them the civilized races — they’re the ones found living together in the towns and cities of civilization. Goblins, orcs, gnolls, and kobolds — along with plenty of other races in the Monster Manual — were never part of that human empire. Some of them, such as the militaristic hobgoblins, have cities, organized societies, and kingdoms of their own. These are islands of civilization in the wilderness, but they are not “points of light.”
Magic Is Not Everyday, but it Is Natural.
No one is superstitious about magic, but neither is the use of magic trivial. Practitioners of magic are as rare as fighters. People might see evidence of magic every day, but it’s usually minor — a fantastic monster, a visibly answered prayer, a wizard flying by on a griffon. Powerful and experienced practitioners of magic are far from commonplace.
Gods and Primordials Shaped the World.
The primordials, elemental creatures of enormous power, shaped the world out of the Elemental Chaos. The gods gave it civility and permanence, and warred with the primordials for control of the new creation. The gods eventually triumphed, and primordials now slumber in remote parts of the Elemental Chaos, rage in hidden prisons, or float, lifeless, through the Astral Sea.
Gods Are Distant.
Gods exist, though most of them maintain a distance and detachment from the everyday happenings of the world. Exarchs act in the world on behalf of their gods, and angels appear to undertake missions that promote the agendas of the gods they serve. Gods are extremely powerful, compared to mortals and monsters, but they aren’t omniscient or omnipotent. They provide access to the divine power source for their clerics, paladins, and other prayer-using followers, and their followers pray to them in hopes that they or their exarchs will hear them and bless them.