Traveller’s rules imply a great many things about the setting, but there are two that are tossed out as being true:

1. Traveller is “Age of Sail in SPAAACE!”
2. Traveller is “Feudalism in SPAAACE!”

Addressing the first one first: This is an easy claim to back up, and is primarily due to the speed of communications in the setting. When everything is at least a two-week round trip away at best, you end up with a setting that has various far-flung posts that are linked by the vessels that are carrying the messages. This is indeed reminiscent of our own history prior to the invention of the railway and the telegraph.

This is not an exhaustive listing of all the types of science fiction, but some hopefully focused rambling on what considerations one might have in a science fiction setting. It is focused mostly on thinking about things in terms of tabletop role playing games, but probably applies more broadly to fiction as well.

One possible approach is to look at large setting elements (things like aliens, spacecraft, space travel, cybernetics/transhumanism) and decide how you want to deal with them. This has nothing to do with the rules one is using, at least not directly: if you wish to make a SF-flavoured Dungeons and Dragons, it is extremely doable. So we will talk in generalities about some options for some of the big questions, and how they might be addressed. If one wants a whole book, with worked (instead of illustrative) examples, check out GURPS Space.

Much of this is adapted from the ATV rules in Across the Bright Face.

Basics

Mechs are a type of vehicle and use the Vehicle (Mech) cascade skill. While a variety of designs exist, most are about 10 tons in weight and about 4-5m tall. They can travel at about 80km/hr consistently, with only extremely rough terrain slowing them down. They normally have only a single pilot.

Mechs are generally a little complicated and finnicky. They require maintenance once a week or after any combat in which a hit is taken. Maintenance is a mechanics throw; failing (or not doing maintenance) penalises any DMs by 1 per missed maintenance window.

oldhawkeyes put together a great post about combat styles in Classic Traveller. When it was first posted, I threatened to make some of my own, so here here we are. Some of my fighting styles use special abilities from oldhawkeyes’ post, because CT is generally fairly breezy, and needing to remember a squillion special attacks is just a pain, even if they are player-facing, so adding too many should be avoided.

It bears repeating.

One of the cheapest ways to build depth in a TTRPG setting is to reuse things. Need to introduce a NPC? It was the one that the PCs ran into a few sessions ago. Need a temple? Use the one that they went to get healing from before. Want to reinforce a theme of some kind, say oppressiveness? Have them get stopped by the guards. Again.

That is it, really. The rest of this post is some examples and expanded thoughts, because I can not leave well enough alone, and so I need to over-beat the egg with more words.

Many Traveller adventures (and in similar systems/settings) are geared towards the PCs being fresh out of a career, with ‘assets’ amounting to massive debt, a half-collapsing rust bucket of a ship, and someone who can give them a job that might not kill them. Sometimes they do not even have the ship (but common advice is to get one fairly quickly: the game is titled “Traveller” after all). Incidentally, a similar thing happens in the various OSR scenes: there are squillions of starter dungeons and one-page adventures and so on, but very few published adventures aimed at sustained high level play (and even fewer good ones).

There have been a few people who have asked about starting Traveller. This needs something to be asked of them before answering properly: do they mean Traveller-the-setting or Traveller-the-rules.

Traveller-the-Setting

Traveller-the-setting is something that is dealt with in the mainline Traveller editions, starting from a loosely sketched out one in 1977’s Little Black Books and running through to Mongoose’s recent second edition revised. This provides increading details about Charted Space, the Official Traveller Universe (or Original Traveller Universe). There are of course a few digressions on the way, such as GURPS Traveller being an alternate timeline, GURPS Interstellar Wars being a jump back to the early part of the setting, Traveller 4 which is set around the start of the Third Imperium, T20 which is about 200 years before the the original (and current Mongoose) edition. Most of the official Traveller material is set in around 1110, give or take a few years, with earlier editions from Game Designers Workshop pushing that timeline forward through to around 1248. Mongoose has come back to the 1110s for their own published campaigns.

One of the major hassles folks seem to have when running factions in RPGs is deciding what they are trying to do and what assets they have available. One possible framework for thinking about this is to steal from the military, who need to evaluate threats within an area on a routine basis. There are a few frameworks that are in common use (and someone has already covered one: SMEAC). This post will look at the METT-TC framework, along with some examples.

Charted Space, the Original Traveller Universe is big. It is pretty too big for most practical purposes. There are a few ways to approach this. The most common is to find places that are more interesting for games to take place in (I have some suggestions for interesting places my intro to Classic Traveller post). One can also just roll up your own setting, which is the assumption in the original books. This post if going to talk about a few considerations of how to shrink the whole OTU setting down to something more manageable.

One thing that might be useful for thinking about in SF settings is what information ships broadcast. While all sorts of things could be, a good model for what information might be valuable is to look at the Automatic Information System (AIS) used by shipping here on Earth. This is a transmitter that broadcasts a position and other identifying information reguarly, originally for collision avoidance, but which is now used for a variety of other things.