August 21, 2025

Out of Time!

It has been an age and a bit since I last posted anything to this blog aside from the monthly collection of daily fantasy roleplaying gaming tips I drop on BlueSky and Mastodon dice.camp. The primary reason for that is that I’ve been working like a maniac as the lead editor for Draw Steel, the MCDM RPG. In fact, I’ve been working like a maniac on Draw Steel since late 2024 (and loving every minute of it), but the last four months or so have been especially filled with time crunch.

In a gray stone cavern, four glowing purple cauldrons stand around a wide black pit.

Despite that time crunch, though — and despite the downside of being so flat-out busy working with other wonderful folks that I run out of time to work on my own stuff — I still manage to run two CORE20 games every week on top of a D&D 5e game I’m playing in. And when you’re running low on time to sleep, finding time to prep the games you’re running can be a challenge.

For one of my CORE20 campaigns a couple of months back, I ran five sessions of built-from-scratch homebrew adventure, set up with about two hours of prep. Not two hours per session, but two hours for all five sessions — fifteen or so solid hours of gaming. And now that I have a bit of downtime again, I thought it would be fun to break down my process, which covers a number of specific approaches I’ve found useful for prepping games when the amount of time you have to prep games approaches zero.

The Framework

A while back, I talked about a framework for fast game prep that can help you create a solid two-hour one-shot session in less than 10 minutes. The process I’m going to talk about here reflects that approach to some degree, but expands to the idea of prepping multiple sessions for an ongoing campaign, not just creating single-session adventures.

Is it possible to treat a homebrew campaign or adventure as an excuse to never stop writing notes, ideas, NPCs, monsters, history, and more? Yes it is. And it’s fun to do so if time permits! But what I’m talking about here is a minimalist approach where what you’re looking for is the maximum return on your time, in the sense of being able to say, “This five minutes of prep will let me fill an hour of game time.”

Home(brew) is Where the Heart Is

As a general setup, fast prep is almost always about homebrew adventure design. Because over many years of running games, one of the odd truths I’ve discovered is that running your own homebrew adventures takes less time commitment than running published adventures. On the face of it, that might seem odd, given that published adventures do all that writing and story design stuff for you. But the reality is that doing the kind of close study and notetaking you need to really get a feel for a published adventure and a sense of how you want to run it takes a lot of time. Certainly, for a great adventure, that can be time well spent. But when your time budget is flat broke, something’s got to give.

Being only half-prepared to run a published adventure can be a tense experience. But being only half-prepared to run a completely homebrew session can be exhilarating, because you get a much better return on your creative investment from making things up on the fly than you do from looking things up on the fly as you try to remember where your published adventure is meant to go next. 

Lay of the Land

To build out an adventure quickly, start with a cool map. Or, as I did for the multiple sessions I needed to plan with no time, start with several maps you can easily link together. Two types of maps are ideal for fast prep — those with straightforward features that don’t require a lot of notes (wilderness, caverns, simple dungeons), and those that are so detailed you can just pull information off the map (detailed city locations, manor houses, fortresses, and so forth). Avoid locations such as a wizard’s tower where you’re going to need to think up a bunch of wild details to support that location. You want to be able to wing that sort of information on the fly, whether you’re coming up with generic details for an underground grotto, or saying “There’s an oak chest in the corner of the sitting room” because that’s what the map shows.

For my campaign, I scored five maps from Dice Grimorium — one of a number of cartographers I back on Patreon — all part of a “Cave Tunnels” series. Then I let the maps springboard the other fast-prep components of the extended adventure.

A map showing gray stone caverns and tunnels set with glowing green crystals.

Thematic Inspiration

When you’re putting together a full adventure in a hurry, focus on a singular theme that you can use to suggest monsters, traps, and other mechanical components, and which you can easily fall back on as inspiration when you’re talking up description and mood. For my adventure, the cool colored crystals on the map immediately suggested “elemental caverns,” so that’s what I went with, setting up different colors of crystals on the different maps. One level each of earth caverns, water caverns, air caverns, and fire caverns. Then inspired by the theme, I grabbed a final level taken from a similar map series showing four eldritch cauldrons around a vast pit (seen above), which I decided would make a most excellent power source for the elemental caverns above.

Fight the Good Fight

If you’re playing any sort of campaign in which monster hunting is the characters’ jam, planning combat-focused sessions is one of the best ways to maximize your prep time, because setting up combat is way faster than the time filled out by running it.

While the characters figured out how to cross a chasm in the earth cavern, I decided that they’d come under attack from transfixers — the CORE20 upgrade to the piercer, which first magically dazes you, then launches from the ceiling to arc through the air toward their targets like a stalactite air-to-surface missile. It was a monster the characters had never encountered before, making the fight feel fresh, and a good fit for the location and the earth/rock theme.

For the water level, I worked up a tougher-than-usual wight guardian — breaking from the elemental theme in order to introduce a mystery (talked about below). For the air level, an air spawn (the CORE20 air elemental) was on guard and perpetually pissed at anyone trying to steal valuable elemental crystals (talked about at “Treasure” below). 

For the fire cavern, the elemental crystals embedded into the walls were the threat, erupting with energy randomly whenever the characters got too close. These weren’t set up as traps, though, but effectively static combat threats that the characters were fully aware of, then needed to “fight” their way through.

The combat encounters through the elemental caverns were fairly straightforward in terms of threat level. So then for the cauldron cavern, I got to break out the big guns for a climactic challenging encounter — a fiendish vrock drawn to lair within the flow of magic boiling up from the well and through the cauldrons. Oh, and each round, the cauldrons would lash out toward a random character with elemental energy — though not in the way they expected (see “Treasure!” below).

It’s a Mystery

Setting up a simple mystery the players can ruminate on and solve is a great way to heighten engagement — and comes with the benefit that players thinking through a mystery are doing most of the work while you play. For this adventure, the combat with the advanced wight led to the discovery of another group of wights, all previously destroyed (and thus inert), but with no signs of battle around them. Each showed wounds consistent with having been executed while alive, allowing them to be transformed into wights by corrupting magic in the cavern. But each had also then been executed again as a wight, with no signs of struggle or having been bound.

The strange nature of this seeming sacrifice was something the players latched onto immediately, and generated an awesome amount of discussion around what circumstances might have caused it. The truth behind the mystery — which the players figured out in good time — was that this was a group who had discovered the caverns, become corrupted by the energy of the cauldrons when they used one to destroy an enemy army above the site, and were transformed into servants of the cauldrons’ magic. The group collectively decided to end their lives rather than follow the cauldrons’ directive to leave the caverns and become walking conduits for destructive elemental power, with the advanced wight the last survivor. But if the players had come up with another explanation that felt even more dramatic, I would have absolutely made use of that instead. That kind of course correction in response to figuring out a mystery is a special gift to the GM who doesn’t have time to prep, wherein without even knowing they’re doing so, the players write up the backstory you didn’t have time to figure out. 

Raise the Stakes

The final piece of the no-time-to-prep prep process was setting up a clear conundrum for the players to deal with. This came in the form of the cauldrons, with the dead-wights mystery and the scouring elemental power witnessed during the vrock fight confirming that the magic of the site was far too dangerous to just walk away from. Dumping the cauldrons into the pit was an obvious solution to that problem, but doing so incorporated the challenge of each cauldron being too heavy for any one character to move, and programmed to lash out with corrupting power if anyone got too close. 

Destroying the cauldrons using a careful approach of moving in behind them, lassoing each of them in turn, throwing the rope across the pit, then pulling from the other side played out over most of one session — literally two minutes of prep time to set up a couple of hours’ worth of planning and roleplaying. Part of the reason that worked is that the characters had no access to any magic that could have destroyed the cauldrons outright. But if they had, I would have simply adjusted the cauldrons’ potency to make sure that a certain amount of discussion and problem-solving would remain.

Treasure!

The final piece of the campaign-building puzzle is the rewards to be bestowed upon the characters for facing off against the challenges you’ve laid out for them. Looking to your theme and your map locations for inspiration is a good starting point for rewards, and I did so to come up with two ideas. 

First, a certain small number of the elemental crystals found throughout the caverns had become saturated with elemental power that would remain in them if they were removed. With a sense that these special crystals would be valuable assets to crafters creating elemental-themed magic items, the characters were meticulous in locating and claiming them.

Second, the theme of elemental power and the idea of the wights having been corrupted by that power to become servants of it set up the idea that during the final fight, the cauldrons lashing out against the characters wasn’t actually an attack. Rather, it was an attempt to infuse the characters with magic that would eventually tie to them to the cauldrons as corrupted servants. For the first couple of cauldron “attacks,” the characters made their saves and so knew nothing about this. But when the first character failed their save and found themselves gaining the ability to cast a variant-damage fireball, the fight got more interesting. When one of the characters then realized that the power they were absorbing was tying them to the cauldrons, the fight got more interesting again.

Game On

It’s literally taken me longer to write up this post than it did to prep the fifteen-or-so hours of gaming whose setup I’ve described here. Doing campaign prep is fun for me, and I don’t begrudge myself time spent making notes, sketching out ideas, and assembling the building blocks of a cool adventure. But even if you’re like me and think of campaign prep as time well spent, focusing on a simplified framework for adventure design can be a good experience — especially when you find yourself in a time crunch and need a different approach.