A list of sci-fi, space-fantasy or OSR-space games I've seen at over the years. Generally these include both human and non-human races and the possibility of interstellar travel as a standard part of the universe.
Although some may have been left out, this list is compiled with an eye toward exhaustiveness. Some of these games cover similar material, but with a little different style, or geared toward different system preferences.
Some I'm familiar with, others only in passing. Some I've presented opinions about, others only given a brief blurb based on a skim or seller description. So if you find something not quite right, feel free to comment.
OSR Games - Old School Renaissance, retroclones & similar games.
Bandits and Battlecruisers - Hodgepodge of old school bits and pieces. A bit of interesting stuff here and there.
Encounter Critical - A love letter to early era homebrews and the indiscriminate enthusiasm for sci-fi and fantasy. Free.
Hulks and Horrors - Excellent. Follows the Race = Class model. Includes three non-human PC species. Heavy on modifiers. Has some interesting tables for generating star systems, planets, habitats, treasures, etc. Now free and open source.
Humanspace Empires - A bit rough. Apparently an offshoot of Tékumel, but offworld in the normal universe.
Null Singularity - Excellent. Not technically a stand-alone game, Null Singularity is a one-off adventure, using a lighter system loosely based on the Dungeon Crawl Classics (DCC), with significant modifications. It puts players in the position of spacers aboard an ark-ship intended to preserve humanity against a bizarre, universe-destroying event. The goal is ultimately a test of perseverance in the face of near hopelessness.
Rogue Space - Not exactly a retroclone. Relatively lite sample game though. Free.
Scavengers & Spacewrecks - A microgame based on the Searchers of the Unknown system. Free.
Searchers in Space! - Also a microgame based on the Searchers of the Unknown system. Free.
Space Princess - Odd little sub-sub-genre:
Machinations of the Space Princess - Have not read, but got a lot of press awhile back. Prides itself on a little sleaze. Reviews claim it to be very flexible, though one described a default setting of"Barbarella meets Star Crash meets Ice Pirates meets Star Wars".
Tales of the Space Princess - Excellent. I got a copy of this. Neat, and pretty straightforward game in the spirit of Star Wars and serial pulp adventure. Has adventure generators. Also in PDF.
F*** the King of Space - A bit rough. Despite the initial profanity, another seeming normal OSR style labor of love game. Maybe not really a "space princess" game. The title would seem to suggest it's the contrapositive of the genre. Free.
Space Ryft - A bit rough. Mentioned for the sake of thoroughness. Free.
Star Dogs - Mostly rules that are a somewhat modified version of OSR type games. Not heavy on setting details. However, certain bits suggest an implied setting similar to Star Wars, but with an even more decadent Empire and a sort of Chaos-wielding cult in place of the Jedi:
StarSiege - Space opera based on the Castles & Crusades engine. Have not looked this much, but the intro PDF is free.
Stars Without Number - Excellent space opera game (not so much with the aliens though). Version linked is free. Updated versions may not be.
Mandate Archive - Supplements that add different dimensions to the setting.
Two-Page Space - What it says on the tin. A bit like a skeletonized version of Stars Without Number.
Universal Decay: Dead Stars - Maybe not really OSR. But part of the OGL exuberance of the D&D 3E era. Intended as kind of a space-horror setting. Doesn't really hold my interest well, mechanically or setting-wise. Mentioned mainly because I looked into it quite awhile back. There's a free version dated some years ago, though the text and layout is monotonous. Also apparently a newer version for sale on Amazon?
White Star - Built off Swords & Wizardry rules. Also got a lot of press, though I hadn't read it in much depth yet. As of this writing there is a free version.
Outer Space Raiders - A bunch of material supplementary to White Star, or probably any other OSR game you're interested in.
X-plorers - Excellent OSR-ish game. An earlier game than White Star. X-plorers is a light yet thorough game of space based troubleshooters. Has simple rules for starship chases. Mechanically similar to OD&D/Swords & Wizardry.
D&D in Space - Not just using a similar system to the D&D games, but more specifically taking the fantasy genre (or elements there-of) and getting it into space somehow.
Between Chains and Starlight - From the description, this appears to be a third party Pathfinder equivalent of Dragonstar. Available as pay what you want.
Dragonstar - Excellent D&D 3rd Edition game. Assumes that high technology is works best for many applications that fall within the laws of physics and magic for things that technology can't help with. Also rationalizes the prevalence of various gods and fantasy races on different planets. While I'm not the hugest 3rd Edition fan anymore, this game is my favorite combination of space opera and magic.
Space Age Sorcery - Excellent. Excellent? Well, I love it at least. This is not a stand-alone game, but a bunch of spells to add to your existing old-school game giving it a weird science, ancient aliens & cosmic entities vibe. I wouldn't say these are designed with game balance in mind, many are oddly powerful or have unpleasant side effects. Still, I love the idea of adding them to a game. Free.
Spelljammer - High fantasy settings entering space via flying boats (or sometimes cool organic-ish, aquatic-looking-animal ships). Phlogiston, crystal spheres, and crazy not-at-all science physics all over. Not my favorite D&D setting, but it has quite a few fans.
Starfinder - Paiso's space opera game based on their successful Pathfinder fantasy game (itself based heavily on D&D version 3.5). I'm not very familiar with Starfinder. My impression is that Starfinder retains the races of Pathfinder and some of the magic, but shifts tones down or shifts the focus away from them to the more sci-fi trappings of the setting.
Terminal Space - OSR-ish game. Setting a weird sort of D&D/Sci-fi hybrid. Free.
Voidspanners - Essentially a Spelljammer supplement for the Basic Fantasy retroclone. Free.
Star Trek Specifically
Official - Material officially licensed at one time
FASA Star Trek - Out of print, I believe. The original Star Trek RPG. I knew the system at one time, but it has been too long. This would probably have only covered the original series and maybe movies.
Decipher Star Trek - Also out of print I think. I still own this book. It uses the CODA system, basically a non-OGL quazi-clone of the d20 System (roll 3d6 instead of 1d20 for most checks). The game was intended to allow play in any era from the original Star Trek series, through Voyager. Characters were generated through sort of life path series of menu options, which seemed pretty well thought out.
Unofficial - Materials giving something of a Star Trek feel, though not officially licensed. All interesting though:
Far Trek - OSR-ish Star Trek. Free.
Five Year Mission - A supplement for White Star (see specific entry for White Star) to give the game a more Star Trek slant.
Lasers & Feelings - Light, quick generation, narrative, off-brand Star Trek focused a bit on crew interaction in a crisis. Free.
Galactic Hinterlands - My own hack of Lasers & Feelings. A bit more expanded but less polished. Free.
Star Explorers - A 1982 Star Trek homage. Reviews don't highly recommend it except as an adventure generator.
Starships & Spacemen - Another Star Trek homage RPG:
Original (1978) - Unofficial, but probably the first Star Trek RPG.
Second Edition - Written much more recently. Word on the street is this is mechanically more closely based on Labyrinth Lord (a B/X D&D retroclone). Apparently covers both original series and next generation styles.
Where No Man Has Gone Before - OSR-ish Star Trek. Free.
Star Wars - Also offshoots of the same.
Edge of the Empire - Uses it's own unique system.
d20 & Saga Star Wars - Used the d20 system or variants there-of. Not currently available to my knowledge.
d6 Star Wars - The original d6 System Star Wars RPG created by West End Games has recently been reissued.
Other Stuff
d6 System - Originally derived from the West End Games version of Star Wars.
d6 Space - This appeared to be derived from Star Wars with all the identifiable details filed off when they lost the Intellectual Property rights. It is basically generic space opera material.
Mini Six - A lighter, more flexible, universal variant of the d6 system. Intended as more universal than space opera focused, does cite a few specific NPCs which would fall into that category. Free.
Apocalypse World Engine / Powered by the Apocalypse (PbtA) - This more modern system seems to have a few space opera related supplements:
Adventures on Dungeon Planet - A Dungeon World offshoot. I think this might technically be more directed toward planetary romance genre, but has some tropes which might work for space opera.
The End of Known Space - A bunch of aliens and locales to go with the Adventures on Dungeon Planet game. I was drawn by the cover art.
Battle Between the Worlds - Specific campaign rules for Adventures on Dungeon Planet, which would eventually give rise to Space Wurm vs. Moonicorn.
Space Wurm vs. Moonicorn - An offshoot of Adventures on Dungeon Planet, focusing on relationships between a galactic tyrant, a rebel upstart, and various intermediaries.
Farflung - Seems to be another post-human far future. Maybe more focused on individual impulses and relationships. Cool illustrations though.
Impulse Drive - Basically another general space opera. Description sounds like characters defined more by setting role in general rather than alien race and class. Pay what you want.
Uncharted Worlds - Seems to be a human-centric game of exploration, profiteering, social unrest and corporate intrigue.
Big Eyes, Small Mouth (BESM) - A sort of universal system intended to emulate a wide variety of anime genre. BESM went through several editions of increasing detail and complexity (ending in Tri-Stat dX), each of which could be probably be used to run space opera one way or another. However, the game also included a couple supplements which skew more directly to the genre:
Drifting Through Space - A relatively simple system with some vague space opera trappings. Pretty short on setting details though. Also, the gimmic of having the rules entirely hand written in a tongue-in-cheek, in-character conversational style made them a bit tiresome to parse. Free though.
Eclipse Phase - Relatively hard transhumanist horror/conspiracy sci-fi. Pretty thorough and well thought out world-building. Uses a very detailed, CC licensed d100 system. Version for FATE also available. Free versions also available.
Fading Suns - A bit more anthropocentric space opera about an old interstellar feudal dominion and various specialized human occupational castes within it. Uses it's own system.
Fate - The Fate RPG system has several supplements or entire settings in a space opera vein:
Aether Sea - Essentially Spelljammer, maybe with a tiny smidge less crazy-physics. Pay what you want.
Andromeda - "Humanity has arrived in the Andromeda galaxy in great, slower-than-light space arks . . . You are members of the elite—leaders, scientists, and moral figureheads. Strive to outmaneuver your rivals and deal with the dangers of Andromeda, including alien empires that resist the arrival of human beings." Pay what you want.
Baroque Space Opera - Seems to be an extensive amalgam of Dune and Warhammer 40,000.
Bulldogs! - FATE based. Another game of planet-hopping hijinks. Mainly humanoid aliens. This seems to be a pretty well fleshed out setting, with multiple supplements and editions.
The Great Game - Grand sort of superheroes in space setting.
Mindjammer - "heroic adventurers in the galaxy of the far future, filled with virtual realities, sentient starships, realistic aliens, and mysterious worlds"
Strange Stars - Touts itself as "a setting for any game where modern transhuman science fiction meets classic 70s space opera".
Full Parsec Five - A setting for my Miso-Six game and similar micro-RPGs. Imagine a "standard", mundane FTL space opera setting... Full Parsec Five takes place in the unguessed Astral Plane, basement universe of dead planets, dark matter nebulae, the husks of burned out stars and strange ancient worlds, which underlies that normal universe.
GURPS - As the name implies, the Generic Universal Role-Playing System covers a lot of ground. In the core book alone there's probably enough information to run a space opera style game, although it's not dedicated to that specifically. I'm not super-enamored of the game system itself, but over the years it has generated a vast and wonderful array of supplements covering both real world and fictional subjects too numerous to count. These, I find, are the real joy of GURPS. Many supplements are space opera relevant. These are the few that come to mind:
GURPS Lensman - Based on the works of E.E. "Doc" Smith. I am not well acquainted with this series, but have heard it widely discussed as classic space opera.
GURPS Space - Excellent. Bar none, this is the best book to get to cover all your space-RPG needs. Even if you don't like the GURPS system, this has something to say about different planetary types, political structures, FTL styles, other technologies, sub-genre conventions, etc. I owned two editions at different points in time, and both were great source material.
GURPS Transhuman Space - This is more focused on hard sci-fi and (as the name suggests) transhumanism, than most space opera. I always saw it as the less-horror-based version of Eclipse Phase.
Other GURPS Material - The number of GURPS supplements is so long I won't go into much detail on any others at the moment. Just a quick list of a few others that might be relevant:
GURPS Aliens
GURPS Powers
GURPS Prime Directive
GURPS Space Adventures
GURPS Space Ships
GURPS Tales of the Solar Patrol
GURPS Traveller
GURPS Ultratech
ION Guard - A game of heroic interstellar peacekeepers with versions for the BASH! system or ICONS superhero system.
Main Sequence - Free, simple 1d6 game based on the WYRM system.
Mothership: Player's Survival Guide - A game focused on space ship horror scenarios. Based entirely on d10 and percentile. The illustrations and art style were a nice touch, but the system didn't hold my interest.
Savage Worlds - Folks have argued that you can easily run a space opera type game with just the core book alone. But there are a couple books out there that might be of some use:
Daring Tales of the Space Lanes - A collection of pulp era space adventures.
High Space - A more fleshed out space opera setting.
Science Fiction Companion - Potentially useful to more thoroughly flesh out your own homebrew setting.
Scum and Villainy - Space opera criminal and low-life adventures, uses the Blades in the Dark/Forged in the Dark system.
Space 1889 - Combines the idea of 19th Century imperialistic powers with anachronistic space travel capability. Never my bag, but included for thoroughness.
Space Master - The sci-fi version of the Rolemaster system. Discussion I've seen suggests there were 2-3 editions of the game. In theory a generic, "any sci-fi genre" sort of game. But seems to have had a default space opera setting.
Space Opera - The eponymous game of the genre. Have not looked into it much.
Star*Drive - The space opera setting for the old Alternity system. IMHO the aliens are kinda neat, the setting is okay. Not a personal fan of the system, but I've known folks who were. No PDFs I know of available, but was selling reasonably priced on Amazon last I checked.
Stargate SG-1 - A d20 system RPG built around the Stargate intellectual property. Although I own this, I've never looked at it in great detail. It seemed to cover the setting pretty thoroughly. (Side note: although this has enough of the right elements to qualify as space opera, at heart I'll probably always feel it's more truly a modernization of the planetary romance genre.)
Star Frontiers - Early-ish TSR space opera using a system of it's own (kind of percentile based). The setting is a multi-species alliance, intentionally not in our universe. Art and technology has the kind of classic vibe of what folks in the 1970s-1980s thought cool FTL civilizations might be. The system is passible in general but a bit cumbersome in some spots.
Stoneburner - A game about dwarves re-settling a haunted astroid mine in a universe where magic and technology both exist. As of 5/26/2023, a draft of the game is released to Kickstarter backers, but it is not in general distribution. It is possible for non-backers to preorder though.
TAG Spacers - General space opera game. Relatively small game, but didn't excite me much. Might be personal preference, but for a small system seemed just slightly needlessly complex in certain spots.
To the Stars, Stellar Cadets - Relatively light game, intended to emulate pulp sci-fi serials of the 1930s-50s.
Traveller - Classic game of space travel, exploration, trade, etc. Well historied and much beloved. There are many editions with thematic shifts, probably best to research before investing heavily.
Cepheus Engine - Open Game offshoot of the Traveller system.
Trinity (a.k.a. ÆON) - A futuristic space opera setting by White Wolf, using a variant of the old Storyteller system rules. Though using a similar system Trinity was not part of the World of Darkness. Instead it loosely shared a universe with Adventure! (a game of historic pulp adventure) and Aberrant (an edgy modern superheroes game).
Urutsk - I tend to think of it as Baroque science-fantasy space opera (sci-fi on the surface but crazy-magic-physics all the way down). Official website is here. Originally based on Encounter Critical, Urutsk has undergone frequent tweaks and updates in the past, so you may need to get in contact with the author to track down the most recent version.
Valent Games - Has put out a few entries in the genre, all free or pay what you want:
Star Empire - Short Earthboy helps defeat the evil empire game.
Sufficiently Advanced - Not so much a space opera with aliens, but a future so distant as to be post-human maybe, and with crazy fantastic technology.
Valence - Just a general space opera with it's own unique system. Nothing bout the descriptions and reviews really grabbed my interest. There's also a tiny version.
Vast & Starlit - Very light weight, storygame-ish system, attached to an escaped alien prison transport scenario. The few small rules expansions as well. Really not what I'm looking for, but kind of beautiful little game. More artwork in the same mode as the cover. Pay what you want.
Warhammer 40,000 (a.k.a. WH40K) - The grimdark future with a fasciest human empire squaring off against hostile and/or inscrutable aliens throughout the galaxy. Dangerous psychic feedback, corrupting trans-dimensional gods, ancient empires, etc. The setting has long ingrigued me a bit, even if some of the pessimistically nihilistic overtones aren't really my thing. And product line is largely focused on war games, but some RPGs exist:
Overview - Wikipedia gives a brief overview of all.
Rogue Trader - May be the most "space opera" of them all, as if focuses less specifically on the fighting, and more generally on exploration and alien encounter.
Dark Astral - Notable because it is not actually a Warhammer product, but seems to be a 40K inspired variant of the ZWEIHÄNDER system.
Zap - With a name like "Zap", I thought it would be a small book, light weight system. And there are some simple things about it, but not really a set of mechanics I love. And the details apparently take over 100 pages to flesh out. Plus, in the copy I got, there was a certain lack of polish that I didn't really love. Still, it has plenty of material you could use to run space opera. Free though.