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Stars Without Number vs The Expanse Roleplaying Game

Compare Stars Without Number and The Expanse Roleplaying Game side by side. See differences in complexity, dice, genre, cost, and more.

Stars Without NumberThe Expanse Roleplaying Game
GenreScifiScifi
TagsSandbox, Exploration, Low-Prep, Faction Play, Tactical, Ascending AC, Vancian CastingLicensed IP, Space Opera, Ship-Based, Crunchy, Social Combat, Investigation, Faction Play, Social Intrigue, Strong GM Support, Tactical
Core Mechanic2d6 + skill + attribute ≥ target for skills; d20 + modifiers for combat. OSR-inspired.Roll three six-sided dice, two matched and one differently colored Drama Die, and add an ability score plus a focus bonus of +2 if applicable. The total must equal or beat a target number set by the GM or an opponent's result. Rolling doubles generates stunt points spent on combat, exploration, or social effects. The Drama Die's value sets the degree of success.
Dice2d6 / d203d6
ComplexityMediumHigh
AccessibilityVery HighHigh
RunnabilityVery HighVery High
LicenseProprietaryAll Rights Reserved
Third-Party PublishingNot yet researchedNo verified route found
Summary only, not legal advice. Check current terms before publishing.
CostFree$$
PublisherSine Nomine PublishingGreen Ronin Publishing
Year20172019
LanguagesEnglishEnglish
Best ForSandbox sci-fi campaigns with comprehensive GM tools for faction turns, sector generation, and adventure creation.Groups who want a character-focused science fiction campaign of crew jobs, faction pressure, and danger across the Solar System. It suits tables that want structured action, investigation, and social encounters alongside ship travel.
HighlightsFree version is generous, comprehensive sandbox tools, faction systemBackgrounds, professions, talents, and focuses build characters with mechanical ties to their lives before the campaign begins. Action, exploration, and social encounters each use dedicated stunts, giving different kinds of scenes procedures beyond a single skill roll. The Churn turns accumulated complications into escalating story events, giving the Game Master a structured way to introduce setbacks.
ConsiderationsOSR combat can feel flat compared to modern tactical systems, B/X heritage means limited mechanical support for social or narrative playCombat stunts are drawn from six separate category tables covering roughly sixty options, requiring both players and the GM to check charts mid-fight to keep pace. Ground and air vehicles receive no example statistics, leaving their combat rules almost entirely improvised. The forty-page setting guide summarizes the solar system's factions and history at a survey level, so groups wanting deeper political detail need outside reading of the novels.