Gamma World

Science Fantasy Role-Playing Game

“The first world is lost in the mythical past, the second was destroyed by apocalyptic energies, and now a whole new world awaits you-GAMMA WORLD!” (From the Forward, by Tom Wham and Timothy Jones.)

TSR, 1978 by James M. Ward and Gary Jaquet.

9 1/4 x 11 1/4 x 1 1/4 inch box
56 page rulebook
16 x 25 inch map
Polyhedral dice

Additional items in the museum's collection

Poster of cover
Referee's screen and mini-module
Legion of Gold "exploration module" GW1, by Gary Gygax with Luke Gygax and Paul Reiche III
Famine in Far-Go "survival module" GW2, by Michael Price.
The Cleansing War of Garik Blackhand GW3 by Michael Price and Gary Spiegle
Delta Fragment GW9 by Kim Eastland

Gamma World 2nd Edition boxed set.
Gamma World 3rd Edition boxed set.
Gammauraders boxed wargame (contributed by Joe Miller)

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After the release of Metamorphosis Alpha (MA) in 1976, TSR produced Gamma World, another science fantasy game, in 1978. Gamma World (GW) may be considered a sequel to MA, although it had a far more successful run. TSR produced MA in only two versions, the original, and as a setting for the unpopular Amazing Engine system. Gamma World, however, went through four versions with TSR, plus a fifth version designed for the short-lived Alternity game system which was briefly released before Alternity died. White Wolf's Sword and Sorcery Studios released a d20 edition of Gamma World from 2003 to 2005. As of this writing, Wizards of the Coast is at work on a seventh edition boxed set that is completely compatible with D&D 4th edition (D&D Gamma World).

While the museum has the 1st, 2nd, and 3rd editions of GW, this review is for the 1st edition only. The fantasic, garish cover by Dave Trampier implies a game of discovery and exploration, with danger hovering all around. It was stunningly effective in setting a mood, and TSR sold it as a poster (the museum has one on display). Gamma World was based on many literary sources, including Brian Aldiss's The Long Afternoon of Earth, Andre Norton's Star Man's Son, Sterling Lanier's Hiero's Journey, and Ralph Bakshi's film Wizards.

Like D&D, Gamma World offered a setting where player characters could serve as heroes exploring a dangerous wilderness away from civilization, where awesome mysteries drew adventurers to risk death from horrifying monsters. The death rate would be high, but survivors could expect rich rewards. Where D&D characters would find magical items and gold that could be used to buy better equipment, Gamma World heroes mainly found ancient artifacts that might boost their fighting ability.


The Setting

The background describes a pre-apocalyptic world of wealth, beauty, and leisure in the 24th century. However, bored humans formed special interest groups which began to get political, and fanaticism, intolerance, and bomb-throwing developed. Finally, a mystery group named The Apocalypse ordered the world to stop fighting or they'd destroy it all. The squabbling world took offense, located the Apocalypse base, and so the world ended in a burst of nuclear weapons and mutagenic devices.

Okay, so the background story was a bit cartoonish. The point was to create a world where there was a near complete disappearance of any social order outside of small communities, where the remnants of super-science could be pitted against superpowered mutations and horrible monsters. As an revision of MA, Gamma World's setting provided for more space for overland travel, a greater ratio of "natural" to "artificial" environments, and new kinds of organized opponents in the Cryptic Alliances. It took away the pure human advantage of having followers (now everybody can try for followers), but made explicit the pure human advantage of being recognized by most robots and ancient technology as somebody to be protected, not destroyed.


Character Generation

Gamma World's mechanics were explicitly designed to be compatible with AD&D and “Metamophosis: Alpha to Omega” (the vaporware upgrade of MA as an expansion to GW). The mechanics were cleaner than MA's and stripped out nearly all of the unnecessary complications that AD&D added to original D&D.

Players generated characters with statistics on six personal characteristics, using 3d6: Mental Strength, Intelligence, Dexterity, Charisma, Constitution and Physical Strength. These stats are practically the same as D&D's, with only Wisdom removed, replaced by Mental Strength. The rules recommend that no characteristic be below the average score of 9-12, and encourage character generation with 4d6, taking the best 3 dice. As in MA, players get to choose to be an unmutated human (or Pure Strain Human, PSH), a humanoid, or a mutated animal.

After generating one's stats, non-PSH characters generate mutations. Two techniques are given for mutations. The first uses the old MA system: roll 1d4 each for physical and mental mutations, pick them, and the referee chooses 1-2 defects based on the number of mutations the character has. The second has players roll their mutations at random. Since the mutational defects are listed on the tables, a lucky player may have no defects, while an unlucky one may end up with a worthless character and have to start over. As in MA, the PSH is at a disadvantage for not having mutations. GW compensates for this a bit by giving them a +3 bonus on Charisma, and nearly universal respect from robots and other intelligent technology—if they're operating properly. Mutant animals selected as PCs automatically get "Heightened Intelligence" at no cost to bring them to the same level as the rest of the group.

The mutation tables are longer than MAs, even excluding the defects. There are 49 physical and 49 mental mutations. Not all mutations are equally likely (there is a 1% chance of rolling chameleon powers, but a 6% chance of getting heightened strength), and the percentages differ depending on if you're starting from a human base or an animal one. There's also a handy plant mutation table, with percentages, for creating plant monsters. PCs are still forbidden to be mutant plants.

As in MA, one gets a d6 for hit points for each point of constitution, and this is a fixed quantity that is unlikely to increase much.


The Combat System

The combat system is MA's with a few changes. You determine the attacker's weapon class, which is a number assigned to the type of weapon you have. Weapon class ranges from one to sixteen, with lower scores (clubs, hammers, spears) being less effective than higher classes (fusion rifles, micro-missiles). You also determine the defender's armor class, which ranges from one to ten, with lower numbers indicating more protection. Then the referee cross indexes weapon class to armor class, obtains a to hit number, and players roll to beat that number on a d20. The armor class table uses the same 1-10 armor classes of 1st edition AD&D (for compatibility), but it's not entirely clear that the numbers mean the same thing: does AD&D platemail and shield (AC 2) really provide the same degree of protection as GW's powered alloy armor?

For attackers using claws or other non-weapon physical attacks, there is a second table to cross index attacker hit dice to defender armor class. Weapons damage is parallel to 1st edition AD&D, with different damage numbers based on whether the target is man-sized or larger.

Mental attacks work about the same as MA, too: cross-index attacker's mental strength against the defender's on a table, and there is a resultant to hit number to beat on a d20.

There are two innovations in GW combat. The first is fatigue: after battling for more than 10 melee rounds, characters may receive a penalty on their weapon class as they become fatigued in combat. Larger weapons will fatigue more, and wearing armor also provides for fatigue. If weapon class drops to zero, the attacker must withdraw and rest. Notice that there is not a linear progression for weapon class, however: dropping from class 8 (grenades and javelins) to class 7 (robotic tentacles) is equivalent to a +4 to hit! Since fatigue from attacking only applies to non-power weapons, which only cover weapons classes 1-3, this isn't too much of a design flaw, but a character in armor wielding a crossbow (which has a high weapons class) may find it easier to hit after getting tired out in combat.

The second innovation is a simple morale check, with the referee rolling a d10 to see if the opponents flee: a roll of 5 or more is needed for non-intelligent combatants to stay in the fray, and a roll of 3 or more for intelligent opponents.



There is a decent number of monsters listed, and of course, more can easily be generated using the mutation tables. In MA, these opponents were given simple names: “Cougaroids,” “Sword bush,” “Blood Bird,” but in GW, creatures get cryptic names like “Blaash” (a deadly moth-creature that emits intensity 18 radiation, killing nearly everything within 5 meters of it), “Orlen” (a two-headed humanoid with nasty powers), or “Horl Choo”, a mutant plant that can crawl about and hurl 3 meter-long spear-like spines at opponents.

Gamma World also had organized opponents: the Cryptic Alliances. These are poorly described bands of sentients who seek some political goal, such as the Knights of Genetic Purity, who seek to exterminate all mutant humans, the Friends of Entropy, who wish to exterminate all life and mechanical operations, or the Followers of the Voice, who worship computers. Referees had next to no information on these alliances, and had to develop everything about them without assistance, although there was a wonderful story in The Dragon #9 about the Friends of Entropy and their leader, Blern the Stranger.


Hazards and Rewards

As in MA, environmental hazards such as poison and radiation have a strength of 3-18, which is compared to the constitution of the defender. If the defender's constitution is one to three points more than the toxin, the defender takes some dice of damage, but if the toxin is equal to or better than your constitution, the character is instantly dead. There is a small chance that radiation exposure will lead to another mutation instead of death.

GW has an extensive list of technological goodies to be found. However, finding a device is only half of the fun. There are a series of three increasingly complicated flow charts, and players must roll to navigate them. A high intelligence permits bonuses to the die rolls. If the marker makes it to the end box, the PC has learned how the device works. However, there are a few skull and crossbones scattered through the charts, and meeting one of these means the device has injured the PC, sometimes with fatal consequences.

The last part of the book features information about the Gamma World. There is a short table describing the cost of a few common items, priced in both “domars” (the pre-holocaust unit of world currency) and gold pieces, unminted chunks of gold weighing an ounce each. As for D&D, GW talks about relatives who might inherit a deceased character's possessions, and a common tongue for all sentient beings.

GW re-introduced experience points and character advancement, although this was very limited. With enough experience points, players could roll on a table to get +1 to a randomly selected ability, or +1 to hit, or +1 damage with melee weapons.


GM Aids

Finally, there is a short section of tips, including a small outdoor map, a map of a tiny military base's grounds (the building's interiors are not mapped), a description of how a referee might start out the group, detailing their home tribe, and an example of play which focuses on exploring the military base. Open the door, search for treasure, fumble figuring out the laser pistol and narrowly avoid killing a fellow PC, and set off an alarm that will summon wandering monsters. There are some tear-off pages with useful charts and tables, and a surprisingly useful list of pre-generated encounters and some totally worthless artifacts for players to puzzle over: a carton of bars of soap, an instant movie camera that is obviously broken, a “3-dimensional animate-inanimator — perfect condition, never used, including rechargeable solar battery (built in).” These random artifacts are never explained.

There is also a lousy map included in the box, with a distorted USA shown, with markings for the mountains, rivers, and primary technological installations. The scale is so huge that there's no question of terrain, and the lack of detail isn't going to inspire any campaign to travel far to go from one empty part of the country to another.



In play, some of GW's innovations didn't work. Fatigue added another complexity to combat, and was often disregarded. The flowcharts for figuring out artifacts were clever, but they slowed the game, and players felt it was entirely too much random die rolling, with no opportunity to make any decisions other than to gamble on more rolls or abandon the device. The character advancement system was inadequate to mollify D&D players expecting real improvements in their abilities, and the low provision for healing coupled with massive amounts of damage again made it difficult to get too invested in one's character, because sudden death was always a possibility.

While it's possible to play a low-key game of GW, this is not entirely under the control of the referee. If players get some of the more powerful mutations (such as the dreaded life-leech, which sucks hit points from everybody within range and adds them to the mutant's own hit point total), the referee is forced to throw large numbers of high-powered opponents at the party to make combat a challenge. This puts a referee who prefers not to run a high-power game in a difficult spot: if players are permitted to choose their mutations, they are likely to come up with balance-busting combinations. If players are not permitted to choose their mutations, they may lose interest because they are not interested in their characters. After all, mutations are as fundamental to the character concept as super-powers are in a superhero game.

A subtle feature of GW is that it minimizes the role of the dungeon. In D&D, PCs are expected to plumb the dungeons to obtain enough power to be able to survive the wandering monsters outdoors, where there is as much risk of running into powerful monsters as weak ones. In MA, the entire setting is a dungeon, and the natural sections tend to be small and quickly cleared out. But a typical GW campaign has players starting in the outdoors, and technological installations (dungeons) tend to be smaller, less common, often well guarded and incredibly dangerous. For the first time, there is more sense in exploring the outdoors than in plunging into dangerous, monster-haunted dungeons.

Gamma World hovers between being a success and being a failure. Each revision lasted for only a couple of years before the support died again, yet after a hiatus, a new edition would be produced. Without sales figures, it's hard to see exactly how popular GW was. It seems to have been TSR's second most popular RPG, and with D&D, it is the sole survivor of TSR's offerings to be re-produced by Wizards, most recently in 2010 using the popular D&D 4.0 engine.

It's easy to find webpages for Gamma World with all kinds of goodies. We suggest going to the Gamma World webring; this is an excellent entry site:


Personal Comments from the Curator

I love the concept of Gamma World. There's something appealing about the post-apocalyptic landscape that repeatedly draws me back to it, and it repeatedly fails me. This is because both MA and GW are games about fighting bigger and bigger monsters, and in this, they are failures. D&D is better at this because the game is always built around the idea of balancing monster threats against player ability, with the PCs gradually increasing in power. I haven't seen this carried out successfully in Gamma World, with the possible exception of the 2010 edition. In order to do it, monsters and artifacts need to be clearly rated in terms of their power level (as in D&D 3's Challenge Rating), so that threats can be built gradually against increasing character power. Once this problem is solved, we're back to the problem of healing injury. Without magic, it's difficult to justify healing characters quickly.

I hope that the new version of GW succeeds. If the designers are careful and avoid the pitfalls of the previous editions, they could have a winner on their hands.


Revised September 25, 2010.

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