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ALIEN RPG vs Gamma World

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

ALIEN RPGGamma World
GenreScifi, HorrorPost-Apocalyptic, Scifi
TagsFear & Stress Mechanics, Survival, Deadly, Atmospheric, One-Shot Friendly, Gritty, Licensed IPSuperpowers, Random Character Creation, Classless, Gonzo, Comedy, Tactical, Grid-Based, Combat-Heavy, Beginner-Friendly, Deadly
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 a d20 and add a modifier, then compare the total to a target number or one of four defenses: Armor Class, Fortitude, Reflex, or Will. Two randomly rolled character origins combine to set starting ability scores, skills, and powers instead of a chosen race and class. Alpha Mutation and Omega Tech cards drawn from a shared deck grant each character's most powerful and unpredictable abilities for the session.
Diced6 dice poold20
ComplexityMediumMedium
AccessibilityMediumMedium
RunnabilityHighVery High
LicenseAll Rights Reserved (20th Century Studios license)Proprietary
Third-Party PublishingNot yet researchedNot yet researched
Cost$$$
PublisherFree League PublishingWizards of the Coast
Year20252010
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.Groups who want a silly, fast-paced pickup game with randomly generated mutant heroes rather than a long-term character build.
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 settingAlpha Mutation and Omega Tech cards replace a fixed power list, so a character's abilities shift unpredictably as cards are drawn, used, and discarded between encounters. Rolling two random character origins instead of choosing a race and class produces unplanned combinations that push players toward improvised character concepts. A hundred-item Ancient Junk table turns ordinary scavenging into a steady stream of small, flavorful rewards between the rarer Omega Tech finds.
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 editionCharacter origins are rolled randomly from a fixed table, so a player who wants a specific concept must ask the Game Master for permission to choose origins instead. The starter box's 80 cards are the only power pool for groups without the two out-of-print expansion kits, capping how many distinct Alpha Mutations and Omega Tech items a table can draw. Running combat means tracking multiple readied and discarded card piles for each character in addition to the four defenses, conditions, and forced movement of the underlying 4th Edition engine.