Inner Worlds table

While we’re waiting for an official fix for the Inner Worlds Table in the Shackleton Expanse Campaign Guide (in case you haven’t noticed, it’s a duplicate of the Outer Worlds Table, both on p. 305), I thought we could share some homebrewed replacements for it. Here’s what I came up with:

1-4      Class Y (Demon Planet)
5-9      Class H (Desert)
10-19    Class N (Acidic Atmosphere)
20       Class L (Marginal)

I kept it simple. The inner worlds in our own solar system are Mercury and Venus, so most of the table is based on those two archetypes. I wasn’t sure if Mercury would classify as Y or H, so I split the difference, giving H a slight edge, so that the more dramatic “Demon Planet” is also the less frequent one. Class N | Memory Alpha | Fandom describes Venus as a textbook example of Class N, so that was pretty straightforward. Since the Outer Worlds Table had a 1-in-20 slot for a Marginal world, I did the same here for symmetry.

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Well-spotted and corrected!

Only comment I would make is that in the real universe, as revealed by recent exoplanet surveys, there are plenty of systems with hot gas giants (class J) orbiting really close to their suns.

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This is a nice alternative table.

(There was a bit of a talk on this topic in the “‘Hex-Crawling’ the Shackleton Expanse” thread, but no real acknowledgement that the printed material was in error).

I may steal this.

BCing you

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Oh, sorry. Thought I’d posted this a while ago. Will update the PDF eventually, but here’s the correct info for the table.

Inner Worlds Table
D20______Inner Worlds
1 ________Class Y (Demon)
2-3_______Class B (Geomorteus)
4-6_______Class N (Reducing)
7-11______Class J (Hot Jupiter)
12-16_____Class D (Barren) or Asteroid Belt
17-19_____Class H (Desert)
20_______Class L, K, or M

Note: If you roll a result that lists multiple choices, you may choose one that fits a story you wish to tell.


You were right!

Thanks so much! There’s a lot more variety here than I thought of.
And of course I should have checked Memory Beta as well. There it turns out that Mercury is considered Class B geomorteus planet | Memory Beta, non-canon Star Trek Wiki | Fandom

Yay. Thanks for posting that.


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Take this for what you will (as this is my very first post on these forums), but here’s my take:

Inner Worlds Table
d20 _____Inner Worlds
1 _____Class Y (Demon)
2-3 _____Class B (Geomorteus)
4-6 _____Class N (Reducing)
7-11 _____Class J (Jovian)
12-16_____Class D (Barren) or Asteroid Belt
17-19_____Class H (Desert)
20 _____Class G (Geocrystalline) - roll d12 on Geocrystalline World Evolution table

Geocrystalline World Evolution
d12 _____World
1 _____Class G (Geocrystalline)
2-3 _____Class K (Adaptable)
4-5 _____Class L (Marginal)
6-7 _____Class M (Terrestrial)
8-9 _____Class N (Reducing)
10-11 _____Class O (Pelagic)
12 _____Class P (Glaciated)

I like very much that Class O worlds are included in this list since they’re not in the “official” list of planet classes in the Star Trek star charts book (the title of which I can’t recall at the moment).

Star Trek: Star Charts. :slight_smile:

…Right, I knew it was something like that. :grimacing:

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Having taken a closer look at Dominus’ chart, I was a bit thrown by needing a d12 of all things. Then I remembered this.

Elan: “The poor d12. So maligned, so misunderstood. Shunned by its more popular d6 and d20 brethren, even the d4 secretly laughs at the poor twelve-sider.

The d4: (loudly/not-so-secretly): “LOSER!”

Elan: “The d3 gets more play and it doesn’t even exist!

Actually, the d3 does exist now; I have 2 of them (as well as 2 d12 dice) in my dice collection for The Gaia Complex, which uses something called the “12.3 rules system”…which uses 12 siders and 3 siders, go figure.

This of course begs the question of whether someone can be expected to own a 12-side die when STA is a 2d20 system…

…Oh who am I kidding, we’re all geeks here: of course we all have obscure and impractical collections of dice! :crazy_face:


I have a d14 somewhere…

For the expressed purpose of getting this thread back on track (preferably before it goes even further off the rails), here’s my revised Inner Worlds table (plus my take on the Outer Worlds table):

Inner Worlds Table
d20 _____Inner Worlds
1 _____Class Y (Demon)
2-3 _____Class B (Geomorteus)
4-6 _____Class Q (Variable)
7-11 _____Class J (Gas Giant)
12-16_____Class D (Barren) or Asteroid Belt
17-19_____Class H (Desert)
20 _____Class E (Geoplastic): roll d20 on Geoplastic World Evolution table

Geoplastic World Evolution
d20 _____World
1 _____Class E (Geoplastc)
2-4 _____Class F (Geometallic)
5-8 _____Class G (Geocrystalline)
9-10 _____Class K (Adaptable)
11-12 _____Class L (Marginal)
13-14 _____Class M (Terrestrial)
15-16 _____Class N (Reducing)
17-18 _____Class O (Pelagic)
19-20 _____Class P (Glaciated)

Outer Worlds Table
d20 _____World
1 _____Class L (Marginal)
2-5 _____Class C (Icy Geoinactive)
6-14 _____Gas Giant: roll on Gas Giant Type table
15-18 _____Class D or Asteroid Belt (Icy/Rocky Barren)
19 _____Class P (Glaciated)
20 _____Class Q (Variable)

Gas Giant Type
d20 _____World
1-14 _____Class J (Gas Giant)
15-17 _____Class I (Gas Supergiant)
18-19 _____Class S (Lower-End Gas Ultragiant)
20 _____Class T (Higher-End Gas Ultragiant)


Dom, I just made a PDF of your chart and I cited you as the author and included a hyperlink to this post. If you don’t mind, I’d like to add it to my GoogleDocs as an STA player resource.

Not at all. And if anything, I’d extend that offer to Modiphius as well.

BTW, are you referring to the revised version (with accompanying Outer Worlds table) or the original?

The revised version with the all d20 charts. I cut and paste the whole thing into a Word document file and tried to align the columns. I’ll post a picture tomorrow so you can critique the first draft.

Looking forward to seeing it, Sutehp. On that note, I had another thought regarding the star system generation tables: what about local interstellar phenomena?

One of the best tools for GMs (at least in my view) with regards to Star Trek RPGs came in the form of Decipher’s own Star Trek Roleplaying Game (which uses the 2d6-based CODA system developed in house by Decipher) - more specifically, the star system generation tables first featured in said game’s Narrator’s Guide and further expanded upon in its PDF-exclusive Worlds supplement. Using this toolset, a GM (or “Narrator”, as they were known in said game) could not only create individual star systems (and the sectors of space they inhabited) from scratch, but also include (whether intentionally or as a result of a die roll) interstellar phenomena unique to each system - spaceborne lifeforms, nebulae, star clusters, wormholes, subspace anomalies, you name it.

Given what Starfleet and the Klingons know about the Shackleton Expanse in general, it opens up the possibility of phenomena unique to whatever star systems lie within. An ancient listening post, asteroids and moons rich in dilithium, a star cluster playing host to a rogue planet teeming with life, even a stable wormhole leading to another part of the galaxy (if not another galaxy altogether) - all these things and more may also lie within the Expanse, and the powers that be (both in universe and out of it) would be shooting themselves in the foot if they didn’t at least entertain that possibility.

What do you or anyone else think?

Yes, of course, one could add a “system feature of interest”-table, just like there’s table 10-4 of the Core Rulebook regarding planet creation. I’d propose to water it down with a second, “exploding” table (“roll on system feature of interest table on a 20”) or to roll whether to include a feature, modified by region and/or star type.

Dom, here’s a jpeg picture of the PDF I created.

Uh, the black background is a result of copying and pasting your list directly off this forum post and I couldn’t get rid of it. :grimacing:

As you can see, it’s pretty rough and no-frills. I figure the next couple of pages should have each Class of planet defined and explained as in either the Star Trek Adventures corebook or Star Trek: Star Charts. Of course, if I make this, its likely to be text only because I’m a bit leery of copying and pasting (not to mention citing!) that much artwork into this document. :woozy_face:

I just took a look at Tables 10-1 though 10-5 in the STA corebook. Maybe these should be included in my PDF as well?