Stocking Hexes with the B/X Dungeon-Stocking Procedure

 The Basic/Expert dungeon-stocking procedure—1d6 for each room, 1-2 Monster, 3-4 Empty, 5 Trap, 6 Special, with a 3-in-6 chance of treasure in a Monster room, 2-in-6 in a Trap room, and 1-in-6 in an Empty room—is a trusty, tried-and-true basic. It's simple enough that I was able to fully describe it in one line, and it breaks down mathematically in a very convenient way, allowing you to essentially write a "checklist" which multiplies out the chances in such a way that all the probabilities are perfectly captured in a block of 18 rooms. Phlox wrote what I consider to be the definitive post on this, though he expands the number to a nice round 20—if I remember correctly, he suggests adding an extra Trap room and an extra Special room.

I like this procedure so much that I use it for hexcrawls, which are, when you really think about it, basically just large dungeons with more freedom of movement. Both involve regimented movement through a defined space, though the time- and distance-units used are scaled up, from minutes and feet squares to days and miles. We expect both to provide a steady stream of discoveries, challenges, and general bedevilments. With a little interpretation and a few additions, the same two die throws that we use to stock dungeons can serve perfectly well to stock hexes.

Preferences for the density of keyed hexes are highly variable. While the procedure I'm laying out here presumes a dungeonlike density of features (33% of hexes marked down as Empty, though "empty" and "not keyed" don't have to be the same thing) it's fairly easy to increase the frequency of Empty hexes to 50% by using a d8 and designating a hex as Empty on a 4-in-8, to 66% with a d12 and 8-in-12, and so on and so forth.

Art from Alariko, sent to me by Morg.

The Basics

I read the standard results as follows: 

Monster hexes are pretty simple to conceptualize—a place with one or more monsters in it—but unlike a 30'x30' room where running into the monsters is inevitable, a hex spanning miles demands a slightly more involved procedure to determine whether you actually run into them on your way through. 

I use the following system: if your system has a %-in-Lair number recorded for monsters, then check it to determine whether the monster is Lairing or Patrolling when entering the hex. If there's more than one monster, it's up to you to decide whether the percentile indicates the chance that all of them will be found inside the lair, or if it's the portion of the band that remains in the lair while the rest wanders. There's always a lair; that's the difference between a Monster hex and a random encounter. If your system doesn't contain a %-in-Lair, invent one for the monster in question based on what makes sense.

Afterwards, roll 1d6, with a result of 1-2 indicates encountering the lair, and 3-4 indicates encountering patrols, or spoor if the monster isn't presently patrolling. These chances can be adjusted based on player stealth, relative speed, monster alertness, or whatever other categories you consider to be relevant.

One neat thing about this is that players can go through a hex without encountering anything and mark it down as Empty, only to stumble into a Manticore lair on a return visit. It's nice to keep them on their toes.

Empty hexes aren't empty in the literal sense. They can contain geographic features, herds of sheep, wild herbs for foraging, friendly farmers, &c. The designation just suggests that there's nothing immediately adventuresome there. Of course, things discovered in Empty hexes can go on to be creatively applied to adventuring—a herd of sheep could be used as a lure for a dragon, for instance—but they aren't intended to pose some sort of particular challenge to the players.

Trap hexes require a bit of creative interpretation. While the presence of literal traps is one possibility—a minefield, for instance—there's plenty of other ways to stock a Trap hex. I tend to use these as a repository for my Man vs. Nature type challenges: treacherous mountain passes, rapids that will dash your riverboat to pieces, a field riddled by volcanic geysers that go off at unexpected moments, or sinkholes that open under your feet and suck you into some wretched sump.

I tend not to like the "canned encounter" (the scripted peril that happens the first time you enter an area, or whatever) so my personal preference is to apply an X-in-6 chance to encounter the trap, guided by how widespread I judge the threat to be. Some Trap hexes might be so dangerous that a trap is always encountered. These chances can be adjusted based on forewarning, particular cautions undertaken ahead of time, or whatever else is applicable. A local guide can often neutralize these challenges altogether.

If a trap is encountered, I'll 'zoom in' and handle the outcome the way I would handle any other trap, with a judicious application of player problem-solving and/or saving throws.

As with Monster hexes, it's neat that it's possible to totally miss a trap on the first run through. 

Special hexes are a wildcard, baby. While technically these aren't supposed to contain treasure, I don't really care what the rules say; a Special room or hex can contain anything you want. That's why they're Special. 

Completely contrary to what I said in the previous entry, I actually don't mind "canned encounters" when it comes to Special hexes—they're Special. I'm fully willing to accept that a special site has some kind of magnetism that draws anyone who enters the area to inevitably encounter it. Of course, something that's supposed to be hidden, like a flower that only grows in a single magical glade in the whole of a deep dark forest, might have a similar X-in-6 chance to be discovered. 

A Special hex doesn't need to be devoid of danger, nor does it preclude the existence of other sentient beings, but unlike a Monster hex these shouldn't really be viable targets for interaction via combat and other such subsystems. The Loch Ness Monster is a Monster hex; the Lady of the Lake is a Special hex.

All X-in-6 chances listed in all of these entries should be rolled upon entry into the hex, and again for every additional hex of movement sacrificed to search the area. A methodical search using proper surveying methods should increase the discovery chance by a cumulative 1-in-6 per each time unit spent, as the players gradually eliminate areas they've already checked.

I trust that Treasure need not be explained.

EDIT: I have been informed that Treasure does, in fact, need to be explained. Since I think that interpreting Treasure interfaces a fair amount with the notion of Settlements, I'll put a section towards the end that will address this more fully.

Settlements

One thing that's notably missing from the established stocking procedure is human settlement, unless you consider a town to simply be a Lair for Traders (HD 1). Initially, I had considered adding Settlement as a hex type, either reducing the chance of one of the existing hex types in order to make room or expanding to a d12. 

This has the upside of requiring very little creative interpretation, but also has the downside of being incredibly boring. What makes this stocking procedure so evergreen is that, rather than approaching it from some naturalistic perspective of describing the literal contents of a room or hex, it instead breaks down space by what the most interesting thing about each location is; what sort of challenge or novelty it presents to the player. It's not "chance to contain armoire," it's "chance to contain trap," which could manifest itself as a trapped armoire.

Designating something as having a Settlement gives you some fairly concrete information about the tangible thing that exists inside the hex—a large, organized group of humanoids and their residences—but very little to guide how the players will interact with it.

I solve this by adding an additional throw, modeled after the Treasure chance.

A Settlement is present...

• ...In an Empty hex on a roll of 1-3.
• ...In a Monster hex on a roll of 1-2.
• ...In a Trap hex on a roll of 1.
• ...In a Special hex if the GM feels like it.

This, again, requires a bit of interpretation.

Monster + Settlement could indicate a settlement of monsters (one might say that this is precisely what a lair is, and the term "lair" itself is a deeply teratophobic construction), but there's other options. A settlement menaced by a nearby monster is a classic, as with Grendel and Heorot, but a little boring; a settlement ruled by a monster, be they fair or tyrannical, is more interesting. A settlement where one or more members are secretly monsters themselves—traditionally lycanthropes or some sort of fish-men, but also doppelgangers, fairy changelings, demons in disguise, &c— is a fairly standard trope.

Empty + Settlement is a normal human settlement with normal human problems. All sorts of adventure could be plausibly mined from this, but there shouldn't be some sort of fantastical, immediate hook here. There's mountains of advice out there for how to invent interesting towns and cities, and you should go ahead and consult some of that.

Trap + Settlement could be a settlement full of traps, like a town anticipating invasion and siege that has filled the streets with Home Alone-style defenses. It could be a settlement surrounded by traps, like a mountain village requiring an extraordinarily dangerous climb to reach, or one of those cool Vietnamese floating villages in the middle of a swamp redolent with explosive gases. It could also be a classic danger like a farmstead of incredibly nice cannibals who will victual the players out of an overwhelming sense of generosity and then, when they're tucked in warm and comfortable in their beds, tie them up and attempt to roast them over an open fire. This last one, obviously, rides the line between "Monster" and "Trap," but I consider it to be kosher so long as the cannibals are complete pushovers in combat—a trap can involve human agency.

Special + Settlement is left up to your imagination.

The size of the settlement can be determined with the same die roll that checks for its presence—the value of the roll gives the settlement size, with 1 indicating a village or hamlet, 2 a town, and 3 a proper city. A simple consequence of this is that Empty hexes will contain the largest settlements, and Trap hexes the smallest, which basically makes sense, since people generally don't actively seek out treacherous hellholes to plant down roots in. 

Settlement chances can be adjusted upwards in particularly densely-settled areas, or downwards for deep wilderness, which also has the effect of altering the maximum and minimum size of settlement. It's also fully acceptable to throw this chance out if you actively want to put a settlement somewhere, or if you want a monster-ruled megalopolis. 

Treasure

As mentioned above, I've gotten some feedback that distributing Treasure in a hexcrawl context might actually require some clarification. 

In general, many treasures will be attached to some site or monster, in which case the placement of treasure flows fairly naturally from however encounters with those things are normally handled. "Standalone" treasures can be handled with the same encounter/search procedure I've enumerated several times before—X-in-6 chance to discover based on prominence, with additional chances allowed by sacrificing movement to search and an escalating discovery chance if methodical surveying is employed. 

But I think some notes on where and how to place the treasure within the context of a hex type would be the most useful, since, unlike a dungeon, it's not always obvious where and how treasure might be found in a wilderness.

Monster + Treasure can always have the treasure be a monster's hoard, kept either in their lair or on their person. This, however, is not the only option. You could have a treasure that the monsters are actively working to obtain, which could result in either an alliance or competition between the party and the monsters. You could have the monster be the treasure, like a golden automaton or a monster whose pelt or teeth or genitals could be sold for a great sum. You could have the monsters lying in wait prepared to steal the treasure once the players have gone through the trouble of acquiring it.

If you're unsure how to proceed, just assign an X-in-6 chance to find the treasure and roll it along w/ the standard check on entering a Monster hex; the joint result can be interpreted fairly easily to work out the relation between the monsters, the treasure, and the party.

Empty + Treasure requires the most clarification. Much of the interpretation hinges on whether the hex is Settled. If it is, the treasure can always be riches or rare resources in the possession of a settlement—oftentimes contained in the coffers and treasure-halls of some local potentate. This sort of hoard can be recovered by burglary, raiding, commerce, revolution, or performing deeds of great valor in the service of the owners.

If the hex is unsettled, then treasure will often take the form of a buried treasure, a sword-in-the-stone type hidden artefact, or a rare resource like a rich vein of silver ore that could be gathered or exploited with diligent effort. Tombs are a good option for both settled and unsettled hexes, though the party will likely face more objection if they try to do tomb-raiding in the former.

For the hidden treasure type, an oft-overlooked fact is that a quarter of all scrolls found, according to the B/X magic item table, will be treasure-maps. This kind of treasure should be near-impossible to discover without a map. 

I would advise against interpreting "Empty" or "without Treasure" too literally. Few six-mile stretches are truly empty, or truly devoid of anything that possesses a monetary value. It's important to remember that "Wilderness Phase" classically begins around 4th to 5th-level, and a standard party of four at that stage requires somewhere in the range of 30,000-60,000 XP to collectively advance a level. Small-scale moneymaking opportunities won't really make a dent in this, and shouldn't be fretted over too much.

Trap + Treasure could have the treasure protected by the trap or the treasure on the corpse of a person who previously fell victim to the trap as easy "defaults." The treasure could be the trap, either in a short-term sense—a solid-gold obelisk that shoots Lightning Bolts at anybody who approaches—or in the long-term sense—a powerful but cursèd runeblade that guarantees weal in war and woe in love. The treasure could also be completely unrelated to the trap; a buried treasure of the ancient Fire Giant civilization happens to be in a volcanically active region with lots and lots of lava flows.

Special + Treasure is left up to your imagination.

Putting it All Together

I chose to put Empty in the "5+" because generally people want to be able to modulate the frequency of encounters, and that number happens to come out to nice round probabilities with all the platonic solid dice. In theory, you could swap it with something else if you wanted a monster-infested wasteland or something. 

Addendum: Double Features

I have long held that every encounter table ought to include a "roll twice" option, so I'd be remiss not to mention this possibility. I tend to think that rolling twice on a table and figuring out how to combine the two results, or how the results play off each other, is one of the greatest tools to get your creative juices flowing, especially when it happens mid-game. 

I can't think of any particularly elegant way to fold that into the existing procedures, an unfortunate consequence of using lots of d6s where there's not a lot of "headroom" in the probability distribution to add another result. You could switch to d8s or d10 and add a "roll twice" function, or you could just roll a second die to check whether or not another roll is called for.

Fortunately, the game already furnishes us with what is more or less a "roll twice" option result via wanderers and random encounters—you can have a perfectly functional three-way standoff by rolling a wandering monster while already in a Monster hex—but that doesn't allow you to have, say, a Trap/Special combo. 

I'd make double hexes a rare treat rather than an everyday occurence.