Deathtrap Dungeon World, Part 1: GM Principles

GM Principles

Although there are some that view Dungeon World as a rules-light “story game” that can be  at odds with the play style embodied by deathtrap dungeons, my own experience with Black Plume Mountain and the Tomb of Horrors has shown that Dungeon World is a uniquely compelling system for running the kind of lethal, competitive delves that were once common in the hobby.

In fact, the GM principles described in the rulebook lay a great foundation for anyone looking to put together a deathtrap dungeon, articulating very clearly the kind of design and gamemastering that is crucial to making deathtrap dungeons vibrant, suspenseful, and memorable. Below, I’ve spotlighted and expanded upon five of Dungeon World’s GM principles, each of which I feel is fundamental to designing and running a successful deathtrap dungeon.

Embrace the Fantastic

The dungeon, especially the deathtrap dungeon, is well-trodden territory in fantasy RPGs. Most players, even those new to the game, are familiar with the trappings of the environment: dusty crypts, hidden pressure plates, pit traps, swinging axes, poison gas, secret doors, and so on. To make your dungeon stand apart from the usual boxed-in, ten-foot-pole fare, resist the temptation to reach for vanilla décor and threats. Instead, take some time during prep to put your own extravagant personal signature on your dungeon elements. Weave a history of mythic bloodshed through your dungeon’s chambers, each of which should defy ethics and engineering. Populate these rooms with unusual monsters and tricks that threaten the characters in sensational, gruesome ways. Most importantly, reward the characters with treasures that have shaped (and shattered) civilization itself. Building a deathtrap dungeon is no time to be conservative or self-conscious.

Give Every Monster Life

Despite the name, deathtrap dungeons are in large part defined by the monsters that lurk within them. In adventures like the Tomb of Horrors, monsters appear much more rarely than in traditional adventures. When they do, however, they need to be terrifying, overpowering, and iconic. When designing a deathtrap dungeon for Dungeon World, don’t just lift a prefab monster straight from the rulebook or your favorite manual. Instead, customize your chosen few dungeon guardians and embellish them with grisly details, heinous instincts, devastating moves, and spectacular death scenes. You should also tie your monsters to the theme of the dungeon and its fronts in a concrete, vivid way.

Fans of the “S” series of AD&D modules have likely memorized Gygax’s famous warning in the Tomb of Horrors that it was a “thinking person’s module” that would make “hack and slay” parties very unhappy. Gygax wasn’t kidding – there are very few monsters in the original adventure, and, in some steadings I ran, players would only roll initiative once every few hours. While converting the adventure to Dungeon World, I made sure to add histories, instincts, front relationships, and new moves to its most famous denizens, including the four-armed gargoyle, the mummy lords, the false lich, and the siren.

Ask Questions, Use the Answers

This principle plays a crucial role in reinforcing to the players the strategic nature of navigating deathtrap dungeons. To make exploration and resource management feel like its own challenge, frequently ask the players questions that force them to interrogate the hard trade-offs they’ll have to make and the holes in their delving strategy. Inquire about what dangerous place they’re thinking about traveling to next, what precious resources they have remaining and what they’re willing to use up, what risks their various options present, and what conclusions they might draw from the limited clues they’ve gathered thus far. Use the answers to flesh out or worsen obstacles the characters will face further on in the dungeon.

Black Plume Mountain, based on the 1979 AD&D adventure White Plume Mountain, has three themed sublevels that the players can explore in any order and leave at any time. While running the campaign, I would often ask the players whether they’d push toward Wave, Whelm, or Blackrazor next, what trade-offs they were making by not exploring the other sublevels instead, what lore they were missing that’d make the puzzles ahead tougher, and how a sublevel’s artifact weapon would help (or hinder) them against the other dungeon lords.

Think Dangerous

This one should be obvious. The fun of deathtrap dungeon play is the rising sense of tension. Players should fear that every element of the dungeon is (potentially) dangerous and feel pressured by the fact that time is ticking away. When running your dungeon, don’t pull punches or shield the characters from their mistakes. Use vicious monsters, lethal traps, and elaborate puzzles – often all at once. Use every narrative opportunity –including soft moves, spout lore, and discern realities – to reinforce to the players that ruin and death wait behind every stone, and that the hourglass runs out with each heartbeat.

Be a Fan of the Characters

While you should kill and kill often, don’t be capricious. Just as you should enthusiastically rejoice when the players stumble into a trap or lament their dead, you should likewise celebrate their victories over your challenges, throw a warm spotlight on them when they do amazing things, and express confidence in their ability to succeed in the face of ever-greater risk. As a GM, you’re not playing to win – like everyone else at the table, you’re playing to “find out what happens.” Trust between the players and the GM is critical to an entertaining deathtrap dungeon delve, so avoid behavior that could undermine this vital but fragile resource.

When running Black Plume Mountain, I’d make sure to spend a lot of time glorifying the characters when they’d solve one of the marilith vampire’s puzzles, slay one of Dragotha’s lieutenants, or claim Wave, Whelm, and Blackrazor. I’d pause to impress upon the characters the gravity of their accomplishments and give each an opportunity to boast about their success and describe how their victory has made them even more extraordinary. These moments were crucial for player morale, so I was careful not to fast-forward through them.

New GM Principles

In addition to the GM principles outlined in the Dungeon World rulebook, I’d like to introduce three more. The following new principles elaborate on aspects of running a deathtrap dungeon that, while not as obvious as the other principles, are just as important.

Great Risk Merits Great Reward

In adventures where the challenges are ratcheted up far beyond the norm, players both expect and deserve rewards to match. Players in a deathtrap dungeon especially need compelling hoards to offset their frequent failures and lend them a sense of progress. The Dungeon World rules already push GMs in this direction, inviting them to create magic treasure that is narratively gripping and confers benefits beyond “mundane” stat bonuses. Don’t be stingy, and take some time to inject flavor into every major reward. You should also add variety to your dungeon’s treasure by placing non-material loot, such as arcane gifts, divine boons, favors, henchmen, titles, or gambits.

Embrace Player Agency and Knowledge

Generally, deathtrap dungeon adventures are more “game-oriented” than traditional adventures. For fans of deadly delves, being asked to rely upon their knowledge as players is not just expected – it’s part of the allure. To this end, don’t be afraid to design challenges that require the players to rely on their own intellectual talents or knowledge of the genre. Likewise, be careful not to shut down any unusual or creative solutions the players might invent to overcome the obstacles in your deathtrap dungeon. Characters in Dungeon World have a lot of moves that generate clues or allow them to seize control of the narrative in their favor, so don’t lock yourself into a single path to victory in such a way that you make these moves useless.

Rule in Favor of the Players, but Never Fudge

While Dungeon World is a rules-light game, there will still be instances where the players will look to you to make a call about an ambiguous situation – particularly if the situation is life-or-death (as they often are in the deathtrap dungeon). In general, you should interpret the rules in a way that benefits the players, if for no other reason than to keep their levels of engagement and enthusiasm high. However, you should under no circumstance fudge a roll or move to protect the characters. Because deathtrap dungeon adventures are more game-oriented than traditional adventures, the fun depends on a sense of concrete danger and brutal fairness. Fudging undermines both.

Delving Ahead

In the next part of this series, I’ll talk about designing monsters, traps, tricks and puzzles for your deathtrap dungeon in a way that embraces Dungeon World’s philosophy and mechanics. I’ll also explain why hard moves are the most important element of your deathtrap dungeon toolkit and present an array of example hard moves you can use in your own delves.


  1. SkoobyDooBop says:

    Greatt to see ya on here Sersa!
    Always lookin forward to your material.

  2. Fright Knight says:

    I’m very excited to see this. An issue I had with running a big dungeon for Dungeon World was that the Thief wanted to search for traps constantly, and I began running out of things to do with that. Also, every time he failed he marked XP, even if there wasn’t a trap.

  3. I can hardly wait for the following posts!

  4. Keep in mind the move’s trigger is “when you spend a moment to survey a dangerous area”. If there’s no traps, it’s not a dangerous area, and the move isn’t triggered, the dice don’t even have to hit the table. Just say “Looks clear!” and keep the action moving.

  5. I am going to have a difficult time waiting for the next instalments. All I can think about today is converting “Murder of the Maelstrom Queen” and how to handle the tiny things about initiative/rounds/movement/positioning which we took for granted in standard Fourthcore because of 4e’s mini assumptions.