Mechanizing the Brothercrawl

03 Sep, 2026

I watched O Brother, Where Art Thou? the other day (good movie, minor spoilers ahead). While OBWAT is openly inspired by Homer's Odyssey, it makes some changes to the structure of the Odyssey to make the resulting story more cohesive. Whereas the Odyssey follows Odysseus's journey between a bunch of discrete islands with weird things happening, the characters in OBWAT have one-off encounters with individuals who end up being folded back into the tapestry of the wider story. And this is what sparked this post, because while the Odyssey can pretty easily be converted into a hexcrawl (Wolves Upon the Coast is pretty damn close), the mechanical structure of the classic hexcrawl does not allow for the more novelistic level of cohesion OBWAT achieves.

Most traditional hexcrawls take the structure of many unlit fuses. The PCs charge into a very tense, but ultimately static, situation, and events that occur are generally the result of their own interventions. In contrast, the characters in OBWAT are constantly happening upon situations already in progress: they meet Tommy after he's supposedly sold his soul to the devil, they meet George Nelson on the way from one bank robbery to another, and there is a ticking clock in terms of the scheduled flooding (and later, the wedding). There is a sense in OBWAT that these events would have still happened, albeit quite differently, had the characters not been present. In this way, we see that the concept of "player agency" and the idea of OSR characters as common, everyday people kind of come into conflict, as most hexcrawls position these characters as the primary movers and shakers of the world despite their low level of (endogenous and diegetic) power.

Of course, in a traditional hexcrawl, if the PCs meet a runaway prince and then later find a cult sacrificing someone with royal blood, the GM might simply decide that it is that prince, even if the original hexcrawl doesn't specify that. But that is a decision made on the level of the GM rather than the adventure designer, and it seems like it should be possible to create that structure in a way that still works with the language of tabletop roleplaying games, specifically those of the OSR variety. I will be discussing a few ways of designing a hexcrawl (or pointcrawl) that come closer to the narrative structure of OBWAT as well as presenting my own.

The Calendar

Let's clarify what we want from a "Brothercrawl":

• Events unfold over time regardless of PC presence or participation
• The PCs can arrive at a situation in the middle or at the end rather than at the beginning.

The most intuitive way to do this is simply to have a clock or calendar that describes how the situation in the hexcrawl changes over the course of the game. This approach is adopted by Desert Moon of Karth, and to its credit, is easy to understand and very blorb-y: everything is set in stone ahead of time. There are a couple issues, however:

• Whoever is making the clock (the adventure designer, or the GM if they are making their own adventure) must do a lot of extra work to prepare the calendar.
• PC actions are disproportionately likely to destabilize the calendar. Say that you have a famous outlaw who robs a bank midway through the calendar, but the PCs get into a shootout and kill her on day 3. Now, the GM has to figure out which entries in the calendar will change (in fairness, it can be great fun thinking about how PC actions have knock-on effects for the whole scenario's future).

The Faction Checklist

One of my favorite systems in Mausritter is the faction checklist, whereby each faction has a set of things they want to achieve, usually in direct conflict with another faction's desires. Between sessions, the GM rolls to see how many ticks to tick off for each objective, causing the situation to dynamically change. I think the faction checklist is a great system, but it's not as imminently gameable as something like the calendar approach. It's mostly up to the GM to determine how these things manifest in the random encounter rolls and hex descriptions themselves, which does avoid the problem of things crashing down when the PCs make big changes, as the GM can dynamically factor those into the rolls for each faction.

The Ticking Timer

Mythic Bastionland's Omens structure is similar to Mausritter's, but much more novelistic: each Myth is kind of a mini-story which progresses from beginning to end, usually an unhappy ending if the Knights don't stop the Myth from unfolding. Each time they travel to a new hex, there is a chance of encountering a Myth's Omen and advancing the clock. Since each Myth is its own timer, while it is possible for Myths to interact, the PC's actions in one Myth are not likely to completely nullify another Myth's Omens. While I think the mechanics of the Myths are very cool, and work very well in that game, I think the fact that things always begin at the beginning and that Omens always happen in the Knights' presence means that it feels like the story of the Myth is happening at the Knights rather than around them, which works for that game but not for the Brothercrawl.

The Hiking Trail

Here is one idea I had for creating something more dynamic than the Calendar but still (I hope) very gameable and intuitive. I call it The Hiking Trail because the ultimate structure looks like one of those little maps you see of all the different trails at state parks and such.

Create a number of different simple storylines and come up with a few steps for each story. Each step should be a specific way the PCs might enter the story through the hexes. For example, in a hexmap of a small kingdom, we might have the story of Jorann, Disinherited Prince:

1. Jorann is Heir Apparent to the throne of Kuzumia and can be found living it up in the palace in the capital.
2. After having been disinherited for falling in love with a peasant boy, Jorann can be encountered on the road to the village of Thrasan.
3. After finding the peasant boy married to a fisherman's daughter, Jorann can be found in his cups at the vile city of Krethar.
4. Penniless, Jorann can be found on the road, hoping to leave the kingdom for greener pastures.
5. Jorann can be found traveling with a group of suspicious pilgrims on their way to a shrine at the edge of Kuzumia.
6. Jorann can be found tied up at the pilgrims' shrine. Come the next full moon, he will be sacrificed by the cult of Arthuvox to herald the demon's coming with royal blood.

I feel like this structure maintains the best of several different approaches already discussed. While it has the same 1-6 format of MB's Omens, I would roll a d6 for each Trail at the outset of the hexcrawl to determine which number to start the Trail at. That way, when the PCs arrive in the region, Jorann might already be disinherited or even kidnapped. Each day or Watch or between sessions, I would give it a d6 chance whether Jorann "decides" to go to the next destination on his journey. If you had 6 Trails, you could even label each 1 through 6 and then have exactly one Trail progress each time you check.

For the record, a Trail can be something other than a single NPC. It could be a group of merchants, a ferocious beast, a strange weather phenomenon, any story that naturally unfolds over about 6 (or however many you want) localized vignettes.

This creates that O Brother, Where Art Thou, connected Odyssey, or Westworld-style structure where PCs might encounter a disinherited prince on the road, then see him later getting drunk, then finally rescue him from an evil cult. On the other hand, they might completely miss him and simply observe the effects of his journey.