THE DUNGEON IS FIRST A QUESTION OF SPACE
The first leg that the classic Dungeon Crawl stands on is “Exploration Play” - a description that points to (or obfuscates depending on how understandable the following is) the Locus of Play in the Dungeon Crawl. Characters in Dungeon Crawl scenarios or games are first explorers - adventurers even - not combatants, designed with abilities and ‘builds’ maximized for destroying specific potential opponents. Nor are characters in the Dungeon Crawl personalities first - they don’t require meaningful information about their pasts or goals (not to say these aren’t potentially fun elements) to play and the Dungeon Crawl isn’t designed with story growth in mind. Exploration play may include a good amount of role play, but it doesn’t focus on emotional character development in the sense of the examination and resolution of character flaws, traumas or desires. It also doesn’t ask the players to deeply inhabit their characters as representatives of a genre - a Dwarf fighter won’t succeed or fail in a dungeon crawl based on how well the player performs aspects of ‘Dwarfiness’ or ‘Fighter’. None of these other types of play are bad, but they aren’t at the core of the Dungeon Crawl experience. Instead the game is found in the characters and players direct interactions with the location itself.
|From the 1st Edition Player's Handbook|
Another way to say this is that there is no overarching plot to provide tension, and no predetermined, expected or rules generated climax that will become the moment of greatest risk and reward. I don’t want to suggest that you can’t have plot or set piece encounters in your game and still incorporate dungeon crawls - but if one is running plotted large-scale narratives it may be best to think as the crawl itself as a single scene or plot point. Nor is this to suggest that characters’ motivations can’t be tied to a location - a character may want to explore a location for personal reasons, and the GM can, even should, still accommodate that. A character’s backstory can be worked into a dungeon - a missing brother may have joined a faction within the dungeon or a lost heirloom might have been stolen away to the dungeon’s fastness - but this is an afterthought. Characters’ individual stories can advanced while exploring the dungeon, character background might even be a useful hook to initially encourage exploration, but personal character stories shouldn’t be the focus - both because this fails to offer incentives for other characters and because the Dungeon Crawl’s Design Principles make scene based revelations and narrative structure difficult to include without forcing the spatial complexity of the dungeon into a linear mold, scattering clues and scenes haphazardly or engaging in sleight of hand that degrades player trust. I don’t want to suggest that a good GM can’t pack a lot of story into a location or that a good location based adventure doesn’t lend itself to creating stories, and I’ll get try to address some ideas about how this works when I discuss the importance of factions in a a Dungeon Crawl, but the Design Principles behind exploration aren’t related to any kind of extrinsic story or narrative.