Terraforming Worlds in The Doldrums Setting

[With apologies for posting later than I wished; I’m on vacation this week, the weather is cooperating (mostly). I’ve been getting yard projects done – finally!]

In the Dumarest Saga by E. C. Tubb, which my Doldrums setting is based upon, many, many worlds in the setting have been Terraformed (planet-formed) during distant eras of humanity’s expansion through the stars.

To simulate this in my Doldrums campaign I was going to create a list of tables and die rolls, along with requirements, modifiers, etc, to simulate a variety of factors, reflecting the potential a world was actually Terraformed.

Upon reflection, it would have been a fair bit of work just to set up, and cumbersome to use, with little actual advantage gained. So I scrapped that idea. Figuring there has to be an easier way, I came up with a much simpler option.


If a world as rolled isn’t ‘optimal’ for human habitation, I use the following criteria to determine if Terraforming has occured. First, the world must be within these ranges:

Size from 3 to 9; Atmosphere from 2 to 9; and Hydrographics under A (10).

Assuming the world falls within these ranges, I allow for One (1) change of its Atmosphere rating, and One (1) change of its Hydrographics rating. We are assuming very high technology was available at some point, as well as time to make these changes, so there should have been ample opportunities for them to have been made.


If Atmosphere is any rating other than 6 (Standard), it changes as follows:

  • 2 (Very Thin) becomes 5 (Thin)
  • 3 (Very Thin, Tainted) becomes 4 (Thin, Tainted)
  • 4 (Thin, Tainted) becomes 5 (Thin)
  • 5 (Thin) becomes 6 (Standard)
  • 6 (Standard) remains unchanged
  • 7 (Standard, Tainted) becomes 6 (Standard)
  • 8 (Dense) becomes 6 (Standard)
  • 9 (Dense, Tainted) becomes 8 (Dense)


For high tech cultures, it is a fairly simple (if time consuming) process to increase a planet’s Hydrographics rating: simply drop a number of ice planetoids on the surface. Removing vast quantities of water, however, is probably not done.

Thus, if Hydro is 0, add 1d3 to it.

If Hydro is from 1 to 3, add 1d2 to it.

Any other Hydrographics rating remains unchanged.


I toyed with the idea of assigning a Compatibility Rating to each world. This would represent the compatibility of local life forms to Terran ones – i.e., how Edible they are. But I decided this was relatively unworkable. This is a GAME, after all, not a simulation.

So instead I decided on a ‘Dominance’ stat. [This may have another name, assigned later.] This represents how much Terran (or Terran-based) life forms have adapted to, or come to dominate, the planet’s ecology. This allows a high degree of familiarity for players, as Terran-style lifeforms are ‘everywhere’ – though they may very well have changed over the millenia.

Basically, I roll 2D, with the following DMs:

  • +1 if Hydrographics 6+
  • +2 if Atmosphere 5, 6, or 8

Results compared to this chart:

  • Less than 8: under 10%
  • 8 to 11: (2d * 5)%
  • 12 or more: (2d + 80)%

This system should suffice for what I want for this setting. While it will make for a number of ‘similar’ worlds, this setting is less about exploring new worlds, and more about human interactions, as well as trying to figure out just what the heck is going on.

Oh, and surviving, of course!


Well, that’s it for this installment regarding the Doldrums setting. As always, I look forward to any discussions, ideas, and the like!

Keep on Travelling!

#traveller #travellerrpg #scifi #scifirpg #classictraveller #ct #traveller20 #t20 #traveller4 #t4 #marcmillerstraveller #gurpstraveller #mtu #dumarestsaga #homebrew #homebrewcampaign #campaignbuilding #mongoosetraveller

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