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ALIEN RPG vs Cepheus Engine

Compare ALIEN RPG and Cepheus Engine side by side. See differences in complexity, dice, genre, cost, and more.

ALIEN RPGCepheus Engine
GenreScifi, HorrorScifi
Play StyleHorror, Survival, Deadly, Atmospheric, One-Shot Friendly, Gritty, Licensed IPSandbox, Modular, Toolkit, Simulation
Core MechanicRoll a d6 dice pool (attribute + skill). Each 6 is a success. Stress adds extra dice — better odds, but stress dice that roll 1 trigger panic. Push rolls to reroll failures but gain stress. Cinematic mode for one-shots, Campaign mode for long-form play.Roll 2d6 + skill level + characteristic modifier. Meet or beat 8 to succeed. Effect (margin above/below 8) determines degree of success or failure. Lifepath character creation with careers, skills, and mustering-out benefits.
Diced6 dice pool2d6
ComplexityMediumMedium
AccessibilityHighHigh
CommunityMediumMedium
LicenseAll Rights Reserved (20th Century Studios license)OGL
Cost$$Free
PublisherFree League PublishingSamardan Press
Year20252016
Best ForSci-fi horror campaigns and one-shots in the Alien universe, with a stress/panic system that mechanically drives tension. Supports both deadly cinematic one-shots and long-form campaign play.GMs who want a fully open, hackable classic sci-fi engine for sandbox campaigns — trade, exploration, and space combat without any IP restrictions.
HighlightsStress and panic system mechanically reinforces horror tension, two distinct play modes (Cinematic and Campaign), Evolved Edition streamlines rules and improves layout, well-supported licensed settingCompletely free and OGL, large third-party ecosystem, comprehensive rules covering personal combat to starship design, fully compatible with classic Traveller material
ConsiderationsTightly bound to the Alien IP with limited genre flexibility, stress mechanics can feel punishing at high levels, Evolved Edition changes are modest over 1st editionDense 200+ page SRD with no setting or adventure content, lifepath character creation can kill characters before play, assumes GM comfort with sandbox prep