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Gamma World

7th Edition
Mutant explorers scavenge a post-apocalyptic Earth patched together from collided alternate timelines
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post-apocalypticscifi
SuperpowersRandom Character CreationClasslessGonzoComedyTacticalGrid-BasedCombat-HeavyBeginner-FriendlyDeadly
Languages: English
Diced20
System Familyd20 System
Cost$
LicenseProprietary
PublisherWizards of the Coast
Year2010
Complexity Medium
Accessibility Medium
Runnability Very High

Core Mechanic

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.

Best For

Groups who want a silly, fast-paced pickup game with randomly generated mutant heroes rather than a long-term character build.

Highlights

Alpha 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.

Considerations

Character 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.