The first Arduin Grimoire starts by explaining how to play Dungeons & Dragons. Sure it claims to be an explanation of how to play “a fantasy game,” but in 1976, when Dave Hargrave penned the tutorial, the range of fantasy games included D&D, D&D set in a world called Tékumel, and a game designed under the generic name of D&D until it reached stores as T&T.

Gamers needed the how-to. The original D&D rules read as a summary for people who already knew how to play. D&D arrived as a companion to a miniature battle game called Chainmail, and the rules built on a foundation of turns and moves. Gary Gygax’s peers felt comfortable with rules for inches of movement and for how many 10-foot squares a character could search in a 10-minute turn. To Gary’s audience, D&D made sense. But the rule books confused folks accustomed to rolling dice to see how many squares a wheelbarrow could move.

Hargrave’s how-to amounts to this: move, roll for monsters, repeat. If monsters appear, roll for distance, surprise, reaction, and then initiative.

As hard as D&D proved to grasp, this “sequence of play” isn’t too different from Risk. Aside from the referee, the game seems nearly as constrained as Clue—except D&D features a hidden board like Battleship.

Ken St. Andre wrote T&T—Tunnels & Trolls—because he found the D&D rules “nearly incomprehensible.” He describes T&T as having the same relationship to D&D as “Chevrolet does to Ford.” His explanation of how to play T&T worked for D&D too. “The game is played something like Battleship. The individual players cannot see the board. Only the DM knows what is in the dungeon.” In 1975, games needed boards. (See 4 popular beliefs Dungeons & Dragons defied in the 70s.)

“There exist numerous enchanted tunnel complexes (call them dungeons or underworlds if you wish) that are liberally loaded with many types of treasure, and abundantly guarded by every imaginable form of monster, magic, and trap. Generally speaking, the greatest treasures and most powerful monster are found further below the surface. Brave men and women arm themselves and venture within the tunnels at risk of body and soul to seek treasure and experience.”

In 1975, games also needed a way to win. St. Andre explained how. “Every time your character escapes from a tunnel alive, you may consider yourself a winner. The higher the level and the more wealth your character attains, the better you are doing in comparison to all the other players.” (See But how do you win?)

Neither D&D’s original rules nor interpreters of those rules describe the loose play of D&D today. They describe a tightly-focused game where treasure hunters enter dungeons, spend turns moving and fighting, and keep score in gold.

From 1974 through the 80s, the evolution of role-playing games marks a move from D&D’s medieval fantasy to universal systems like GURPS, the HERO System, and Basic Roleplaying. In the early 90s, universal systems peaked, and the hobby started moving toward games optimized for one genre or even a narrow range of activities. You could play Kung-fu or vampire campaigns in GURPS, but for many players, optimized systems like Feng Shui and Vampire the Masquerade offered a more compelling experience.

D&D followed the same evolution. Original D&D didn’t aim for the same scope of a modern D&D campaign. The 1974 game arrived laser-focused on dungeon expeditions—and not even on naturalistic lairs, strongholds, and tombs. Original D&D assumed multi-level undergrounds with wandering monsters and rooms stocked randomly from monster and treasure assortments. (See When megadungeons ruled Dungeons & Dragons.) The only rules for non-player characters treated NPCs as monsters to kill or as hirelings to die in dungeon crawls.

Almost everything in the little, brown books supports dungeon expeditions. Sure, the books included rules for wilderness adventures, but as a way for characters to find castle sites. The rules for castles and followers only build a bridge to another game—Chainmail. Few players crossed that bridge. Even subsequent editions of D&D largely ignored it.

As a focus, the dungeon crawl proved a massive success. Dungeons provided an evocative environment with built-in threats and rewards. Plus, dungeons kept characters on that secret board behind the DM’s screen. The walls made the game manageable for new DMs, and all but two DMs were new. (See How the dungeon crawl’s advantages propelled Dungeons & Dragons to success.)

Even though the D&D’s turns and hidden boards felt familiar to gamers in 1974, the game’s wide-open possibilities captured the imagination. In D&D, players could attempt anything. Hardly anyone held to the rigid structure or stayed in the dungeon. A city, The City State of the Invincible Overlord, became the first setting for D&D. (See A butcher, a baker, and naughty nannies in the City State of the Invincible Overlord.) By 1977, Chivalry & Sorcery offered rules for everything in a medieval fantasy world, from kings to peasants, and from jousting to courtly love. That game stemmed from a D&D campaign where players had tired of dungeons and embraced the larger world. (See Chivalry & Sorcery: What if Gary and Dave had not found the fun? Newer games with more realistic combat systems even made dungeon crawls too lethal to be a campaign’s focus. (See The Brilliance of Unrealistic Hit Points.)

As the role-playing hobby broadened, D&D’s scope grew too. By 2000, third edition arrived late to the universal system party. D&D became a branch of the d20 system, which extended to modern settings and Star Wars role playing.

By 2007, the trend toward systems optimized for a narrow range of activities reached D&D and its fourth edition. This version returned to the narrow focus of the original game, but with a completely different choice of optimal activities. Now the game focused on designing characters capable of dynamic battlefield stunts, and then showing them off in combat encounters. Dungeon expeditions became an interchangeable backdrop for combat encounters and skill challenges. This new focus drew criticism from players who felt that a miniature skirmish game, or perhaps a video game, had replaced the original role-playing game. Sure, most players knew you could run fourth edition in the same wide-open style as the prior editions, but plenty saw the new focus as a sign that D&D no longer invited role playing.

Today, D&D returns to a comfortable balance between the sharp focus of the original game and the sprawl of d20. Rather than optimize a system for a narrow focus, the game seeks to embrace three pillars of exploration, combat, and interaction. The game is bigger, but you can still dungeon crawl in the original style—as long as you can live without 10-minute turns.