The Expanse Roleplaying Game — Hard sci-fi on the AGE engine

"Crew, cargo, and conspiracy across a fractured Sol system."

Dice3d6 (AGE)

Players3–6

Prep~30 min

Foundry VTTCommunity

Complexity

What is this system

The Expanse Roleplaying Game brings James S.A. Corey's hard science-fiction saga to the table using Green Ronin's Adventure Game Engine. You play a scrappy crew of Belters, Martians, and Earthers chasing work, secrets, and survival across a divided Sol system. Every test rolls 3d6 plus an ability and focus against a Target Number, with one Drama Die driving cinematic Stunts. Fortune softens the blows instead of hit points, while the GM's Churn steadily tightens the screws until the crew's careful plans go sideways.

Setting

It is a lived-in future where humanity has spread only as far as the Sol system. Earth's teeming billions, a militarized independent Mars, and the exploited Belters of the Outer Planets circle one another in a cold, resource-hungry standoff. Play centres on an ordinary ship's crew caught between these powers, navigating scarce air and water, protomolecule mysteries, and politics that can turn a salvage run into an interplanetary incident.

What it looks like at the table

Naomi jacks into the airlock console as station security closes in. The GM sets a Target Number of 13; you gather 3d6 — one of them the red Drama Die — and add Intelligence plus the Technology focus. The dice come up 5, 5, and a 4 on the Drama Die: 14 beats the TN, and the doubled fives trigger Stunts worth 4 Stunt Points, the Drama Die's value. You spend them on 'Skill Stunt' and 'Take Extra Time', sealing the hatch and looping the alarm before the marines round the corner.

Playstyle

Narrative Action Exploration Space

Key mechanics

3d6 and the Drama Die

Every test rolls three six-sided dice plus an ability and any relevant focus against a Target Number. One die, the Drama Die, stands apart and powers the game's signature Stunts.

Stunts

Roll doubles on a successful test and you earn Stunt Points equal to the Drama Die, spent from menus to disarm foes, land extra hits, or seize the narrative spotlight.

Fortune

Instead of hit points, characters spend Fortune to shrug off near-misses, boost rolls, and bend luck, modelling cinematic close scrapes rather than slow, grinding attrition.

Ships and the Churn

Detailed spaceships and space combat sit beside the Churn, a GM meter that tracks rising trouble and decides exactly when the crew's plans go sideways.

What people say

Not only is it a solid game for presenting The Expanse, but it is a good ruleset for hard sci-fi games in general.— Jared Rascher, Gnome Stew

I also enjoyed my first encounter with the AGE system and thought it worked very well here.— Graham Gibson, Geek Native

It’s a smart game that gives a slick sci-fi experience without veering into the realms of fantasy-with-laser-beams or leaning too heavily on the complex, rules-hungry aspects of the genre.— R.M. Jansen-Parkes, Drop Lowest

Art & materials