Hex-crawls as Mega-dungeons – Part 1

Dungeons have been the foundation of D&D play since its inception, providing some valuable features. There is the ability for the novice DM to draw some rooms and connections, populate the rooms with some random monsters and treasure, each isolated from the other, and then run a successful beginner game. There is the value of constraining player movement, limiting it to the connections between locations of interest. There is the level of detail that allows tactical play in both combat and exploration. This scales up to “mega-dungeon” level which also incorporates travel, rather then exploration, and political interaction between factions in the dungeon.

The wilderness has generally been treated as something very different. An amorphous open space where everything is integrated and movement is free in every direction. Hex grids could be added to plot movement and allow exploration by hex crawl, but it just didn’t seem to have the same value for the game master or the players, and tended to devolve to journeys between known points as “cut scenes” with a few encounters on the way maybe.

However, a hex crawl can have all the benefits of a dungeon crawl. Let me show you how I do it.

In developing this I have a debt of gratitude to Justin Alexander for the many articles that have helped me tidy up and refine these views. In particular 5E Hex-crawls, Re-running the Mega-dungeon and Whither Exploration? – The Invisible Pillar of 5th Edition. The section on Encounters in the 5E Hex-crawl essays are used here, so you should definitely read those and know the distinction between wandering encounters and exploration encounters.

Also have a look at Encounter Summoning.

Hex-crawls as Mega-dungeons focuses on 2 mile hexes (the mid scale). Within each hex we will provide a main encounter, or point of interest. In some such hexes there may be several other interesting sub hex locations, all within about 10 minute walks from one node to the next. Encounters and nodes can be actual dungeons of course. Part of the secret is designing a broad brush stroke large scale, and setting up an improvisation context. This allows you to play off the edge of your prep and still have a lot of support from your framing designs.

Let’s assume you are already ok with making and running dungeons. For a beginners guide for that I’ll refer you to Prep Tips for the Beginning DM and then the aforementioned Re-Running the Mega-dungeon.

For a hex crawl that emulates those elements from the dungeon we will start with a two mile region around an existing dungeon, so the lower scale in the tiered approach we will be using. I’ll assume the players have been delving into the dungeon for a bit without much concern for what’s outside it. This is the normal path for a new DM to ease into wilderness play. When you become more experienced you will often start at the large scale (12 mile hexes) and work down instead.

Lets consider using a 6 x 6 hex grid to cover the 2 mile diameter area. Each hex will be one third of a mile across (1,760′, or 59 combat rounds at 30′ per round, or about 6 minutes walk).

Place the dungeon that you have started with somewhere in that grid. At this scale even a large dungeon is unlikely to take up more than 1 hex of area. More often it will just be a dot on the map. A dungeon is usually mapped in 5′ wide squares, so 1 hex represents an area 352 squares across.

What does that look like? The squares in this image are so tiny it probably looks like a field of grey to you unless you have a lot of magnification or a really big screen.

This still fits inside 1 hex, even if you fill it entirely with dungeon.

Here is the recommended grid blank for our 6 x 6 hex space area.

The 6 by 6 hex grid, with 36 hexes labelled 11 through to 66

Note that the hexes are labelled 11 through to 66. If you have a need to pick a random hex from the grid roll 2d6. One dice provides the first digit and the second dice provides the next. Also notice that the grid can tile with adjacent copies of itself to form a higher level hexagonal grid. More about that later.

At this point take a look at the article on 5e Hex Crawl Wilderness Travel.

We are interested in a time scale of minutes for traveling about on our 1/3 mile per hex map, but the speeds in that article give us a good grounding. Here is my own chart for the scale of movement in 1/3 of a mile hexes. I have generalised ground movement and rowed vehicles on water. You can get more detailed than that but I find this sufficient for most groups.

Now about populating this hex grid. First the dungeon entrance, as mentioned, is in one of these hexes. The details of the entrances should be at about the same scale as the dungeon on a separate map (hopefully you have jaquayed your dungeon). All that is marked in the hex grid is which hex it is in.

The hexes are generally filled with the terrain type that covers the 2 mile diameter space, and maybe a water course passes through. You only mark hexes where this does not hold true, such as an area of open grass 1/3 mile across in the midst of a forest area.

Now place about five to eight “points of interest” in separate hexes, and connect them by paths that may be visible or discoverable by players. That does not necessarily mean that players won’t follow different paths, just that these are the ones most likely to follow because they are visible, or easier to traverse, than the surrounding terrain. Lets include trails to the edges as well.

The points of interest are either special terrain features that stand out, or something that can be encountered, or both.

Here is a filled out example. Note its black and white. For your own notes it’s often just a quick scribble, so I’m refraining from doing commercial production style maps here.

I created that off the cuff in about 5 minutes. No idea what is happening in this hex, area so lets quickly create a little knowledge base.

The Terrain is deep forest terrain.

The Bandits will often be encountered at the creek fishing, bathing, washing or fetching water. Some may be encountered at the hanging tree just keeping an eye on passing adventurers. They tend to not interfere with travellers going to the dungeon. Travellers in poor condition and carrying treasure from the dungeon will get waylaid.

The Ogres go to the falls to catch fish and drink, and grump about along the tracks. They can be found at any of the locations. They tend to avoid the bandit camp but quite happily stomp and kick small bandit groups they encounter.

The Falls may have a hidden treasure behind them in a secret alcove. I haven’t decided.

Going off the trails is difficult terrain and, since its all forest here, good navigation is needed to come out the hex side intended, rather than 1 left or 1 right. If its favoured terrain for a ranger then no problem.

Random wandering encounters here will be with things from a general wandering monster table that we can use for any woods around here. Exploration encounters (as per Justin Alexander’s explanation in the 5E Hexcrawl series) will be with nearby keyed encounters (Bandits, Ogres, and perhaps adventurers travelling to and from the dungeon). Walking into the hex of a keyed encounter along a path at this scale means having an encounter with that keyed item.

Here is a quick encounter table for random things in these woods

roll d6 to pick a column, and d8 to choose the row.


1,2,34,56
1Flying SnakeGiant SpiderD6 Centaurs
2Giant Wolf SpiderGiant ScorpionTiger
3D4 GoblinsGiant ToadD4 Giant Boar
4Swarm of InsectsGiant Constrictor Snake2D6 Orcs
5D4 Boars2D6 KoboldsUnicorn
6D4 BearsPoisonous SnakeTroll
7D6 WolvesPantherWill-O-Wisp
8D6 Commoners huntingSwarm of Ravens2D4 NPC adventurers

This is not a lot different to a dungeon. Encounters are often going to be from walking into a place that has a keyed encounter. Random encounters are less frequent (1 check per watch). Players are still sort of going node to node along paths. Yes players can move off track, but its not as handy, and in some places there are still hard and fast barriers. There can be traps and encounters and treasures. The biggest difference is that access to keyed locations is less restricted. Characters may approach from any direction or even from above.

Cool right?

Of course, this small 2 mile area would only likely take one or at most two sessions to explore. We need more.

“Wait!” I hear you say “If I want to do an area 120 miles across that means I have to map out 93,600 hexes! Aaaaaaagh!”

Ok, hold your horses. Not suggesting you do that.

Part 2, Scaling Up

2 thoughts on “Hex-crawls as Mega-dungeons – Part 1

  1. Pingback: Hex Crawls as Mega-dungeons – Part 2 – Strange Flight

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