Dark Nebula Revisited


“Design is an iterative process. The necessary number of iterations is one more than the number you have currently done. This is true at any point in time.” – Dr Dave Akin, Akin’s Laws of Spacecraft Design

The UK is now in day nine of lockdown for coronavirus, and I’m working from home. This means the time I normally spend commuting is available for other activities; I found myself flicking through my slightly foxed copy of the Dark Nebula boardgame, and decided to take another look at it as the basis for a campaign.

Yes, I know, I’ve tried this half a dozen times before and never been satisfied; but I really like the map, and the SF campaigns I’ve had the most fun running in the last 20 years or so have all been in some version of this setting.

When and Where

The campaign is set in a custom version of the Dark Nebula sector, shortly before the start of the Aslan Border Wars in -1118 Imperial (roughly 3400 AD), some 658 years after the official start of the Long Night in -1776 Imperial (2742 AD).

The advantage of this is that it’s a time and place which has never been fleshed out in any detail, so I can do what I like, starting with ignoring the official map for the region. It’s also not too far from Stars Without Number’s starting point of 3200 AD.

I think it works best to start the PCs roughly six years before the wars begin, say in 3394, and advance the campaign in “seasons” each representing one boardgame turn – two game years. In three tries, the furthest I’ve ever got in such a campaign is season five or game turn two, about 3404 or so.

One way to play it that I haven’t tried would be for Traveller PCs to start at 18, newly enlisted, have one adventure per boardgame turn, then pick a skill at the end of it. That would mean game time would pass at two years per session, and open the door to a generational style of game; every dozen or so turns, a new generation of PCs would step to the fore, with their parents and grandparents available for advice, guidance and funding. Sort of “Pendragon in Spaaace”.

Actually, that sounds like a lot of fun, but for it to work, I needed to start it a decade ago.


You’ve seen me do this before… shrink it to one parsec per hex, rotate 180 degrees for better alignment with Traveller canon, and drop the double worlds. Now it looks like this:

If we make Mizah the campaign homeworld, there are natural stages for the campaign based on the group’s jump capability, which dictate how many worlds need to be prepared and in what sequence.

  • With Jump-1 – groups with a free trader or subsidised merchant – Mizah is the main hub for a cluster of five worlds. Six if you count Daanarni, but that’s a one-way trip in a free trader. Let’s call it season one.
  • With jump-2 – groups with a scout/courier – the right-hand half of the map is accessible, up to 30 worlds depending on whether they figure out how to get at the worlds with no charted jump routes. At this stage, in season two, the PCs start getting involved with the Solomani Confederation.
  • With jump-3 – travelling on a subsidised liner or a mercenary cruiser – you have access to 52 systems, possibly more depending on what’s off-map. Now, in season three, they’re also dealing with the Aslanic Hierate in earnest; towards the end of this season, the Aslan Border Wars begin.

If I were to pursue this far enough to have the full set of statblocks, I’d try importing the custom data into the Traveller Map, which should produce some very fine maps indeed. Something else to consider… although I have lined up the hex numbers to give the setup above, the game owes much of its replayability to the fact that players draw geomorphic map pieces and lay them out as they wish, so long as all the jump routes match up. It would be entirely feasible to rearrange the map pieces, say by putting seven of them in a partial circle around The Fastnesses, where Mizah is; one could also duplicate one or more pieces to make a bigger map – at one point Marc Miller was quoted as saying he intended to write an article someday on how to map the whole sector using the boardgame’s geomorphs, if I recall correctly. But I digress.

In the boardgame, jumps are initially only possible along marked, charted routes (solid green lines); I usually rationalise this by saying the map is a 2-D representation of 3-D space, and worlds which appear next to each other may be too far apart vertically for a jump.


Reading the rules very closely this time, I came to the following conclusions.

Primary worlds are:

  • Naturally habitable, and since Classic Traveller really only talks about atmosphere in this context, that means atmosphere types 5, 6 or 8 – the ones you can breathe unaided long-term. (I’m sticking with Classic Traveller because Dark Nebula was published in 1980, so that was the only edition around at the time.)
  • Able to conduct civilised maintenance, which I equate with annual overhauls, and therefore have class A or B starports.
  • Potentially have a division or two of hirable troops. That’s 20+ battalions deployable offworld, and according to JTAS #10, implies a population level of at least 7.
  • The ones with A class starports can build jump-3 ships, because any ship can jump along any route, and the longest ones are three parsecs; so by Book 5 such worlds must have a tech level of at least 12. I would bump this to 13 for the two homeworlds so that the jump troops can have battle dress, although that’s not explicitly mentioned.

Secondary worlds are:

  • Inhabited, but not naturally habitable and so may not have atmosphere 5, 6 or 8.
  • Can’t do civilised maintenance (therefore starport class C, D, E or X).
  • Can’t raise troops (and are thus arguably population 7 or less, as their hostile environments mean they count as one population level lower for raising troops according to JTAS #10; but possibly more depending on tech level).

Tertiary worlds have no planets and no population. Therefore, they must each have UWP X000000-0. Statistically, under CT one would expect there to be 15-16 primary worlds and 1-2 tertiary ones on this map; that suggests to me that some previous catastrophe utterly destroyed half a dozen primary worlds, and in the Traveller setting the obvious candidate is the Ancients’ civil war.

In the boardgame, all primary and secondary systems have planetary defences, which in CT are generally beam lasers; you could argue that implies a minimum tech level of 9, but I’ll argue those weapons could be imported, emplaced by neighbouring worlds, and so on, as I want a low-tech, frontier feel for the region.

Next Steps

That’s as much juice as I can squeeze from the boardgame for the worlds and the starmap; but if I were to generate the actual worlds, I would do two more things.

First, steal physical stats from real planets, hypothetical ones, or fictional ones I especially like. This will mean some of them break the world generation rules, because real planets and moons aren’t obliged to abide by them (yes, Titan, I’m lookin’ at you). It will also mean I could be up and running quickly with detailed descriptions to hand.

Second, at least for worlds near Mizah, I’d aim for one of each of the six basic trade codes in Classic Traveller, in case I felt inspired to do some speculative trading. Later versions of the rules make it progressively harder to isolate individual trade codes like this, as there are more of them and they overlap.

I am still toying with the idea of having parallel stats for multiple games, even though it has been troublesome in the past; it would be easy to add Stars Without Number world tags, and possibly the rest of the statistics as well. And of course Cepheus Light uses almost exactly the same stats as Traveller. The Savage Worlds Science Fiction Companion may also be an option, because in some ways Dark Nebula is a better fit for the SFC than it is for Traveller, specifically:

  • All planets have more or less the same tech level.
  • Ships all have the same capability for insystem movement, and they either have a hypderdrive or they don’t – and if they have one, they can go anywhere in one turn.

This could be a great game, and maybe it will be, someday. Meanwhile, back to the Trojan Reach; it has many of the same advantages, a very similar feel, and someone else has already done the heavy lifting…

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