Hex dungeons & underworlds

I recently read two great posts over at Dreams in the Lich House:
Megadungeon Topology
Dungeons with Hexes

I love the idea, and I’m going to use it, especially for underworlds (my Crimson Sun Underworld, and the Underdark in my Savage North campaign, etc.).

What do you think about it? D1-2 Descent into the Depths of the Earth is some seriously old-school credentials, for sure.

The hex-scale will need to be taken down some; to, say, 1-mile hexes, or thereabouts. Travel speeds will have to changed (use dungeon movement speeds instead of overland movement speeds; use e.g. 1 hour units instead of turns or days travelled). “Intermediate” rules for random encounters will be needed. What other changes or adaptations do you think would be necessary?

I used a megadungeon with hexes when I ran ACKS Oriental Adventures. Stone-Icicle-World (from Miyama Province, in the OA1 gazeteer) was a sprawling underworld that spread beneath the entire province. There were a dozen different dungeons within Stone-Icicle World, while S-I-W itself was handled like in Descent into Depths of the Earth.

It worked relatively well. A few things did, however, bother me:

  1. Because it was supposed to be a semi-mythic underworld, I only put one entrance. This resulted in the explorations of Stone-Icicle World becoming very time consuming as the game advanced, as the party had to go miles in to explore, and then miles back out each time it wanted to return to the surface.
  2. I didn’t have enough branching corridors so movement felt very linear.
  3. Random encounters felt very arbitrary within the hex-corridor, and very inescapable. If the hexes represent, for instance, main thoroughfares of the underworld’s denizens then they should be “safe” for sentients (of the appropriate race at least).
  4. I never quite grappled with the issues of organization of the defenses. For instance, the entrance to the underworld ought to have been guarded like a fortress.

Yeah, I’m thinking of using essentially lairs and minidungeons (as well as larger dungeons of several levels) as “nodes” in huge underworld environments, ranging from Moria-sized to full-on miles and miles of twisting tunnels. I think there’s several scales possible here, and a lot of room to assume logical but unmarked features, like side-passages (for ducking down to escape enemies), etc.

What hex scale did you use for Stone-Icicle World?

Right now, I’m thinking of using this idea in several ways:

  • City-sized dungeons in the Crimson Sun campaign, inspired by the underground cities of Barsoom; maybe 500 to 1,000 ft. per hex.
  • Underground “wilderness” regions in the Crimson Sun Underworld and the Underdark of the Forgotten Realms in a “early 1E sourcebooks only” ACKS Savage Frontier campaign. I’m not sure what scale would be best here; maybe multiple ones? Full-on 6-mile hexes with “nodes” that zoom into the above scale (so another approx. 30x30 hex map would contain the 6-mile hex)…
  • Moria or other similar dungeons in an old-school Middle-Earth Rolemaster campaign.

And a few other ideas, two of which I’ll elaborate on in a separate thread.