The Expanse Roleplaying Game

The Expanse Roleplaying Game is Green Ronin's licensed TTRPG of James S.A. Corey's novels: a crew of Earthers, Martians and Belters working a ship, taking jobs and getting pulled into politics they can't control. It suits groups who want grounded science fiction with real travel times and firefights that can go wrong fast, where the trouble usually comes from people, corporations and governments.

It is a weaker fit if your group wants a rules-light narrative game or deep tactical miniatures combat. The AGE System sits in the middle: a 3d6 roll anyone can learn in a minute, plus long stunt lists and level-based advancement that take a few sessions to settle in.

What the game is

The game is set in the solar system of the Expanse books and TV series, a few hundred years from now. Earth is run by the United Nations, Mars is an independent military power, and the people of the Belt mine asteroids and moons for both while getting little back. Players make characters from one of those three origins and usually share a ship, which gives the group a home base and a reason to keep taking jobs.

Green Ronin Publishing publishes it. Steve Kenson designed the game on the Adventure Game Engine (AGE) that Chris Pramas created for Green Ronin's Dragon Age, Fantasy AGE, Blue Rose and Modern AGE games. Green Ronin calls it a stand-alone game: the core book has everything you need, and it does not require any other AGE book.

Publication history and editions

Green Ronin funded the first edition on Kickstarter between July 23 and August 22, 2018, where 5,714 backers pledged $402,832 against a $30,000 goal. The PDF reached DriveThruRPG in May 2019, followed by a 224-page hardcover. The book opens with a foreword and a short story by the novels' authors, Daniel Abraham and Ty Franck, who have said the setting began as a tabletop campaign before it became a book series. That first edition covers the period of the first three novels.

The current edition is The Expanse Roleplaying Game: Transport Union Edition. It was crowdfunded on BackerKit (the campaign ended October 17, 2024, with $360,727 from 2,364 backers). The 290-page PDF came out on December 18, 2025, and the hardcover was printed in summer 2026, with backer copies shipping around Gen Con and retail listings following. The Transport Union Edition moves the default timeline to the thirty years between Babylon's Ashes and Persepolis Rising, when the ring gates are open and colonists are spreading to new systems. Green Ronin describes it as an expanded core with the same basic rules, and says first-edition supplements such as Ships of the Expanse, Beyond the Ring and Sol System still work with it.

What you need to play

You need one core book, some six-sided dice (three per player, with one a different color for the Drama Die) and character sheets. If you are buying today, get the Transport Union Edition rather than the 2019 book. It covers the whole timeline up to Persepolis Rising and folds in rules that used to sit in sourcebooks.

Two free quickstarts exist. The original Expanse RPG Quickstart (44 pages) has condensed rules, six pregenerated characters and the adventure Cupbearer. The Transport Union Edition Quickstart (38 pages) does the same for the new edition. The first-edition Game Master's Kit adds a screen, reference sheets, pregenerated characters and the adventure The Ganymede Insurance Job.

Supplements and adventures

Abzu's Bounty is a six-part campaign that started as a Kickstarter stretch goal and came out in late 2019; it runs from an ice hauler in Saturn's rings through Earth, Mars, Luna and Titan. Ships of the Expanse adds detail to ships and space travel, Beyond the Ring covers exploration through the gates, and Sol System (2024) covers the governments, corporations and stations of the home system.

A run of short Trades of the Expanse PDFs added occupations such as Bounty Hunter, Scout, Journalist and Pirate. In July 2026 Green Ronin collected and revised them in Crew Companion, which also adds a Hacker trade, black-market implants, a wealth track called Assets and rules for NPC crew. Green Ronin has named Free Navy Conflict and Daemons' Gambit as the next releases.

Digital tools and VTT support

Foundry VTT has The Expanse (AGE) Official System, with character, NPC and ship sheets and drag-and-drop weapons, talents and stunts. Green Ronin also posts free two-page adventure outlines called Expanse Transmissions to its Atomic Think Tank community.

Core rules and play structure

Every test is the same roll: three six-sided dice plus an ability score, plus 2 if you have a relevant focus, against a target number. A simple task might need 10, and a hard one 15 or more. One of the three dice is the Drama Die. It breaks ties, sets how well you succeeded on some tests, and decides how many stunt points you get.

When any two dice show the same number on a successful test, you earn stunt points equal to the Drama Die. You spend them on stunts from lists for combat, chases, infiltration, investigation, social scenes and more: an extra hit, knocking an enemy prone, learning a second clue, or making a contact owe you a favor. Doubles come up often, so stunts are a regular part of play.

Longer tasks use advanced tests, where you add up Drama Die results until you reach a threshold. Challenge tests work the same way, but each failure adds a complication. Play moves between action time (initiative and rounds), narrative time and interludes, the downtime between adventures when characters repair, train, research or build.

Characters and advancement

Characters have nine abilities: Accuracy, Communication, Constitution, Dexterity, Fighting, Intelligence, Perception, Strength and Willpower. You pick an origin (Belter, Earther or Martian), roll or choose a social class, then a background and a profession, which give ability bonuses, focuses and talents. Origin matters in play: Belters handle low gravity well and suffer in high gravity, and Earthers are the reverse.

Each character also has a Drive, chosen from twelve in the book, with a Quality and a Downfall that describe how the character acts at their best and worst. Talents and specializations come in Novice, Expert and Master ranks. There are no classes. Characters gain levels when the GM decides the story calls for it, and each level gives more ability points, focuses and talent ranks.

Money is abstract. Characters have an Income score, and buying something is a test against its cost. Spending too much lowers your Income for a while. Relationships, Memberships and Honorifics are rewards too: a bond with a crewmate gives bonus stunt points when they are involved, and a reputation can help or hurt depending on who recognizes you.

Signature mechanics

Fortune. Characters do not have hit points. They have Fortune, which stands for luck and can be spent to soak damage or to change the result of one die on a roll. Changing the Drama Die costs more. Spending Fortune to win a social scene leaves less for the next firefight. When damage gets past your Fortune you are taken out, and the attacker decides the condition you end up with, from injured to dying. Players can also choose to be taken out early and pick a condition themselves.

The Churn. The GM keeps a Churn pool that grows as Fortune is spent and certain events happen. At set levels it brings in complications: a weapon jams, a rival shows up, the authorities arrive. When it peaks, things boil over and something big goes wrong. The Churn is the game's way of making plans fall apart the way they do in the novels.

Ship combat. Ships have their own qualities, hulls and conditions, and ship battles run slower than personal combat. Crew members take on jobs such as captain, pilot and gunner. Guided torpedoes and point-defense cannons work as they do in the books, so the ship being shot at often rolls to dodge or shoot down the attack. Hurting your ship hurts the whole campaign, which makes these fights tense.

What play feels like

In a typical session the crew takes a salvage contract or a cargo run, finds something they were not supposed to find, and has to decide who to tell. Travel takes days or weeks, so a lot of play happens on board: arguments in the galley, repairs and calls to contacts that arrive with a light-speed delay. Fights are short and can go badly. At low levels a couple of pistol hits will take a character out.

Stunts give action scenes some color. A player who rolls doubles gets to describe the ricochet, the disarm or the clever lie, and that keeps combat from turning into trading damage numbers.

Running the game

The Game Master section has advice on structuring adventures, investigations, hazards such as radiation, and a long discussion of player and GM styles. Investigations are built as a chain of clues that lead to a final location, where tests give extra information or let the group skip steps rather than blocking progress. The book also suggests series frames such as freelancers, military, political and rebellion campaigns, and talks about how much canon to use.

Prep is moderate. You need a job, some NPCs with stat blocks, and a sense of which factions care. The Churn needs a short list of complications ready. The core book's starting adventure, To Sleep, Perchance to Dream, and the free quickstart adventures show the intended structure well.

Campaign fit

The game is built for campaigns. Ships, Income, relationships, memberships and levels all pay off over months, and the Transport Union era gives a group thirty years of mostly unwritten history between novels to work in. A one-shot works fine with either quickstart and its pregenerated crew, but most of the game's tools assume the same characters coming back.

Fans of the books can play alongside canon or away from it. Gnome Stew's reviewer liked that the sample campaign frames are inspired by the novels without asking players to retrace the main crew's story.

Reception

On DriveThruRPG the 2019 core PDF holds a 4.6 average from 102 ratings, 78 of them five stars, and the Game Master's Kit sits at 4.8. The Transport Union Edition PDF had no ratings yet when checked. No major award win for the game turned up.

Gnome Stew recommended it in 2019 and called it the reviewer's favorite version of AGE, praising the advanced and challenge tests, the investigation guidance and the way Fortune and conditions work together. The same review wished the Churn were a pool the GM could spend instead of a set of thresholds. Drop Lowest liked the simple core roll, the stunts and the slow tension of ship battles, but found the stunt lists slowed play until people learned them, noted that only a few crew members have big jobs in ship combat, and felt high-level characters grow more superhuman than the setting suggests.

Where it is strongest

• One familiar 3d6 roll covers everything, so new players learn it fast.
• Fortune and the Churn make luck and complications part of the rules, which fits the setting's tone.
• Strong support for investigation and social play, not only combat.
• A shared ship and abstract Income give a crew campaign a natural structure.
• Two free quickstarts, an official Foundry system and a steady stream of supplements.

Where it can frustrate groups

• The stunt lists are long, and picking from them slows play until the table learns its favorites.
• In ship combat, the captain, pilot and gunner are busy while other crew may have little to do.
• Level-based advancement can make veteran characters very hard to hurt, which sits oddly with a grounded setting.
• It is a licensed game, and its pull is strongest for people who already like The Expanse.
• Two editions are on the market, so check that you are buying the Transport Union Edition.

Content notes

Expect gun violence, death in vacuum, political oppression, terrorism and the body horror of the protomolecule, all familiar from the source material. The core book's introduction spends real time on making sure everyone at the table is comfortable with the content and with each other.

Best starting path

Download the free Transport Union Edition Quickstart and run its adventure with the pregenerated crew. If the group likes it, buy the Transport Union Edition core rulebook and build a crew around a shared ship. Add Crew Companion when players want more trades, or Abzu's Bounty if the GM wants a ready-made campaign.

Research notes

Last checked November 13, 2026.

• DriveThruRPG: The Expanse Roleplaying Game: Transport Union Edition (release date, page count, price, AI disclosure)
• DriveThruRPG: The Expanse Roleplaying Game (2019) (ratings), plus the DriveThruRPG quickstart, Game Master's Kit, Sol System and Crew Companion listings linked above
• Green Ronin: Transport Union Edition PDF release and What's New in The Expanse? (July 2026)
• Green Ronin: Charting the Expanse (stand-alone design, Fortune and the Churn) and The Expanse: The Science of Story
• Green Ronin: Kickstarter launch post and Abzu's Bounty release post
• Kickstarter: The Expanse Roleplaying Game and BackerKit: Transport Union Edition
• Foundry VTT: The Expanse (AGE) Official System
• Gnome Stew review (June 2019) and Drop Lowest review (July 2019)