Designer's Notes: GURPS Infinite Worlds

by Kenneth Hite

Fathers! Your virtues, such the power of grace,
Their spirit, in your children, thus approve.
Transcendent over Time, unbound by place,
Concord and charity in Circles move.
-- William Wordsworth, Ecclesiastical Sonnets, XIV

It seemed like a three-inch putt, a slam dunk, a veritable gimme. All I had to do was take the best of GURPS' pre-existing alternate-worlds material, an embarrassment of riches if ever there was one, and turn it into GURPS Infinite Worlds. No sweat, he thought. The only thing really missing was a really useful, solid set of guidelines for alternate history construction. So of course, assembling and expanding Infinite Worlds from GURPS Time Travel, both GURPS Alternate Earths books, and Chapter 20 of the new Fourth Edition GURPS Basic Set took me twice as long as I thought it would, and likely three times as long as the long-suffering Andrew Hackard thought it would.

Part of the challenge was simply updating everything, and not merely to Fourth Edition rules. (Although that was no picnic in its own right, since I started work on Infinite Worlds before the Fourth Edition was finalized.) I also had to look at the last 10 years of world-historical theory, and the last 15 years of time travel and alternate history SF. For example: GURPS Time Travel predates Harry Turtledove's Worldwar series, and GURPS Alternate Earths predates Jared Diamond's Guns, Germs, and Steel. What I wrote needed to reflect those changes to the genre and the subject matter, to the extent it could. I took this most seriously in Chapter Three, the "Building An Alternate Earth" chapter, which I divided into two main sections. The first, and one of the trickiest to make work, was a random history generation system, modeled after the wonderful random planet generator in GURPS Space. In a game about infinite worlds, it seemed odd that we didn't have a way for the GM to create them in bulk. What I came up with may not be the first such system (I'm fairly sure that Fringeworthy must have one, for example), but it's the first one that actually pays attention to any sort of historical rigor whatsoever. The second half of that chapter is an extended summary of the current state of historical modeling, with as much rigor as possible while exhibiting a massive bias toward usefulness in designing alternate histories. That, for instance, is why there's a summary of the completely daft "biological history model" of Oswald Spengler in there -- it's nonsense, but Poul Anderson, James Blish, and other top-notch SF writers have used it to design future histories that feel real. Other stuff I tossed into the mix included Strauss and Howe's generational history, the "Kondratiev wave" in economics, and as much as we know (not much) about climate change cycles. The result may not be history as we know it, but it is definitely history as I design it, which seems preferable for roleplaying games.

But mostly I adapted, adopted, and improved, as the Round Table motto has it. David Pulver had (very flatteringly) added the Cabal, reality quakes, and a crosstime-capable Reich-5 to the basic Infinite Worlds setting; I had to figure out how they worked in the here-and-now, and how to explain them to people who hadn't read what I had written about them already. Most of my work was just such building on foundations laid by Steve Jackson, John M. Ford, and Dave Pulver. What did the "10 divisions" in the I-Cops and "eight divisions" in the Scouts do, exactly? What's happened to Reich-5's Japan in the last 20 years? How does John W. Campbell's death abort scientific progress, again? I expanded some things, brushed past some others, and knit the result into a (hopefully) consistent whole. Much of it was actually fun -- I enjoyed going into lurid detail on just how Nazi Science Crossed The Feeble Dimensional Barrier. I added relatively few original ideas to the mix: a crosstime mining corporation run by a parallel Cecil Rhodes, a dozen new alternate Earths to play with, some alternate human races (Morlocks, mutants, Neanderthals, super-soldiers), my standard "campaign parameters" discussion, and some more bad guys for the Order of the Hourglass to fight.

I also added a lot of other stuff that came right back out again, when the book shrank from 256 pages to 240. (You may imagine my delighted reaction, having nearly killed myself, and Andrew, to produce the 256 pages in question.) Some of those pages -- yet more alternate Earths (possibly including my "Turtledove tribute" featuring a Gormelite invasion in the 1960s), and my fantasy crossworld setting "Collegio Januari" -- are apparently slated for e23 releases, so I shan't include them here. But some of the deleted gems were too diffuse to make anything but the cutting-room floor, so I present them now to you fine people. The first section is my attempt to add a future to the Infinite Worlds -- the Promelleans, specifically, are a "GM's friend" to help move PC parties from the Infinite Worlds setting into any future-SF type setting. (Steve didn't like them. Ah, well.) The second bit just compiles a few of the Things That Can Go Wrong with dimension or time travel in general. The eagle-eyed may note a bit of Lovecraftian dues-paying in each section -- I say, if you're going to model a genre, you'd better steal from its best.

Two Dooms: The Future

Although the vast majority of Infinity's experience is (somewhat ironically) confined to the present in its myriad alternate forms, at least two "futures" interact occasionally with Homeline's own era. There are, of course, hundreds, if not thousands, of "time travel reports" and "visitor sightings" choking the Patrol archives, some of them even filed by Patrolmen. Of the reliable "UFB" (Unidentified Future Being) sightings, the vast majority falls into one of two categories: the coleopteran travelers, or the Promelleans. Each claims to come from a future that might be labeled "posthuman," although the details are sketchy at best.

These two futures are not necessarily incompatible, but they differ in the few details generally agreed upon, and of course, in their representatives in the Infinite Worlds' present. Indeed, many Infinity researchers believe both visitor groups come from wildly divergent worldlines, and unaware that they have crossed quantum barriers in their journey, have assumed that they have traveled into their own past. Other investigators of the UFB phenomenon tentatively accept the visitors' claims at face value, but argue that the future per se is a constant state of quantum indeterminacy. In short, the future is not just infinite, it's infinitely fuzzy. By this logic, astrally projecting scarabs and blue quantum fogs are no more or less unreasonable than any other possible future, since nothing exists yet on which to base rationality.

This certainly does little to explain anything, but it does let Infinity higher-ups feel better. The notion that some unimaginable posthuman entities are treating the present the way that Infinity treats the parallel Earths -- as a mere backdrop for their own ineffable activities -- is deeply unsettling to some.

Coleopteran Travelers

Millions of years in the future, after the extinction of mankind, the dominant life form will be a coleopteran species descended from the Egyptian scarab, or dung beetle. This is the unflattering tale told by travelers from that future, or rather pieced together from a century and a half of psychiatric records across seven or eight parallel Earths.

According to this fragmented tale, a race of psionic time travelers from another star occupies the bodies of the beetle-things. It sends the minds of its scouts throughout time watching for signs of its enemies, of which little but superstition is known. They travel by means of a one-way projector that disappears after use -- whether it travels with them materially, or vanishes into acausality, is unclear.

Humans possessed by the coleopteran travelers evince total amnesia, accompanied by confusion about the most elementary details of their own culture. They often show language skills they never previously possessed, and their handwriting becomes odd and spiky, as though they were unused to handling pens. These spells last from three to seven years, during which they drain their savings traveling to remote corners of the Earth (especially Australia, the Carpathian Mountains, and the Dakota Badlands) and research the most abstruse possible combination of paleontology, high-energy astrophysics, and occultism. Shortly after completing this program, they return home, lock themselves indoors, and return to their old personalities overnight with no sensation of elapsed time.

Very occasionally, one of these returned personalities will start having nightmares about life in a hollow complex of tubes and passages, in which he has been transformed into an enormous beetle.


The Promelleans are a bright blue quantum fog of distributed nanobots from the 61st century. Whether they are humans using these fogs as their time machines, transhumans who take this form, or alien entities with human-seeming habits and personalities is unknown to Infinity and seems irrelevant to the Promelleans. Their nanobots cannot be harmed by any technology that Infinity is aware of, and have a high magic resistance. Psis attempting to contact the Promelleans wind up unconscious or frozen -- or vanished, snatched to the future by these enigmatic beings.

The Promelleans are timenappers, taking individuals or small groups of people from certain timelines, often saying to those left behind "This one is needed." Such witnesses are almost always all from the same Earth; Promelleans seldom appear to mixed groups of locals and travelers. Promelleans usually take some care not to abduct people in public or flashy ways, although some high-profile historical "vanishings" such as that of the prophet Elijah may be records of Promellean operations. Promelleans may also be behind some of the vanished conveyors from both Centrum and Infinity; they seem to "select" for targets with broad experience across the quantum stream.

Nobody knows exactly what happens to the kidnap victims, although occasional reports exist of encounters with Promelleans speaking in voices similar to those of vanished Patrol personnel. The Promelleans themselves are no help on the matter, restricting their discussions to oracular pronouncements about the "tree of futures," delphic warnings against "the dead time," or vague promises of "a future of all times and worlds." The most consistent element of Promellean ideology seems to be distrust of someone or something called "the Vortun." Promelleans often admonish Patrolmen against "the Vortun agenda" and sometimes kill people who they identify as "Vortun agents." Whether the Vortun are a faction within the Promelleans, a rival race or transhuman entity, or Promelleans from an alternate future, remains a mystery. No reports exist of any Patrolman meeting a self-identified Vortun.

Three Hazards

The Hounds of Time

These semi-material beings travel in packs of two to seven and leave no tracks aside from the occasional claw mark, but give off a strange temporal signature, detectable by tachyon tanks and other systems. They resemble long, thin quadrupeds built of badly overlapping plates of bluish clay with occasional chinks between where nothing at all shows up. Their heads are indistinct, only their snouts, tongues, and eyes appearing with any clarity.

They roam around waste spots in time, the aftershocks of reality quakes, the tangled detritus of paradox or shifted echoes, and the edges of some ghost roads or dimensional highways. If they catch the scent of a time traveler, they will track him across the millennia (at a top speed of 100 million years per day). If they spot their prey on another world, they have to go all the way back to 3.5 billion years ago before the alternate worlds broke apart, and then track him back down the correct worldline. They may nest back in that primordial era. The traveler will feel them approach him from out of time, as if he had the Death Vision spell (p. B251) cast on him every day until their arrival.

When they catch him, they materialize from out of the nearest acute angle and attack with their claws and then try to core their target's heart out with their rough, hollow tongue (which resembles the proboscis of a mosquito, only much larger). It does 2d large piercing damage from the attack, and coats the wound with a bluish saliva which does 2d more points of corrosion damage every round until washed off. For some reason, the hounds do not like to cross curved lines; hiding in a domed structure (or better yet a spherical chamber) offers some protection.

Hounds of Time

ST 16; DX 10; IQ 4; HT 20.

Will 17; Per 17; Speed 7.5; Dodge 10; Move 7.

SM 0; 100 lbs.

Traits: Discriminatory Smell; DR 2; Dread (Curved lines); Jumper (Time); Quadruped; Regeneration (Extreme); Spirit; Striker (Tongue); Talons; Terror 5.

Skills: Brawling-14; Tracking-17.

The Green Zone

However, conveyors don't always work correctly. About one percent of the time, the journey seems to take time. And sometimes, it seems to take a long time indeed, or pass through some other kind of reality entirely (see Fascinating Parachronic Disasters, p. B532). The space between the worlds apparently can have a physical component. Paralabs physicists call it "hyperspace," and note that the speed of light (or possibly the duration of a second) becomes highly variable in that dimension. The few Patrolmen who have been there call it the "Green Zone," and there are rumors that at least one conveyor -- "the Lost Capsule" -- is still there, its crew unaware that they are even missing. Over a pint at Harry's, they say that sometimes the Lost Capsule shows up, faintly, at your own jump point, and then you know something bad is going to happen that trip.

Fortunately, an intact conveyor keeps a closed circuit of its own reality (probably thanks to the parachronic drive in operation), so even if the conveyor passes through the Green Zone, the Patrolmen inside are safe. Of course, not all conveyors are fully intact before a jump, what with suspicious gun-toting locals being not uncommon on the various parallel Earths. The Green Zone can then affect the travelers.

Exposure to the Green Zone forces a Fright Check at -5 on all who gaze into it; the human mind can't process the roiling otherness of it. In addition to any other consequences of the Fright Check, exposure to the Zone can turn its victims immaterial, creating a danger of rematerializing inside a solid object. They might also turn invisible (permanently or temporarily but never controllably). It can also set witnesses on fire (one unfortunate victim burned for 18 days), freeze them in time forever, or reduce them to point-size singularities that shoot off at high speed. Critical failure on the Fright Check should impose at least 25 or 30 points of disadvantages, even if it doesn't beam the poor wretch into a bulkhead. The GM decides whether to make PCs risk such horrific fates, or whether to save the 18-day fire for NPCs in the conveyor. More positively, exposure to the Green Zone can be an opportunity for characters to add psionic or other supernatural advantages (Jumper, Insubstantiality, Invisibility, and a pyrokinetic Innate Attack seem to match the lore) "awakened" or "implanted" by the stress, although a heavy compensatory set of disadvantages would not be out of line either.

Some methods of parachronic travel, notably sailing on the USS Eldridge, pass through the Green Zone and offer little or no protection to crewmen on the "deck" of the craft.

Really Weird Accidents

The Bailey Effect: The travelers reappear instantaneously at the moment they left -- except they've erased their own personal lifeline somehow. Just like George Bailey in It's A Wonderful Life, there is no record of their existence (the equivalent of Zeroed, p. B100), their friends never met them, their mothers never raised them, and so forth. (Characters with Temporal Inertia (p. B93) remain unaffected.) At the GM's discretion, the world might be altered, or others might have saved the transport or thwarted Mr. Potter in their absence. (If one of the travelers invented the time machine, it might never have existed either!)

The Lie Agreed Upon: The travelers arrive in their target era -- except that it's not historically accurate, but a kind of semi-literate Hollywood pastiche of the era. Cavemen fight dinosaurs, the Library of Alexandria has a "Lost Books" section and a card catalog, and Napoleon is always grabbing his stomach and ranting about being short. This can be played for farce, or as a deadly threat to the fundamental reality of the cosmos.

Welcome Back: History has "moved aside" to let the characters in. The opposite of the Bailey Effect; the travelers arrive to find themselves a known and registered part of their target era with friends, parents, and enemies in it. Their new lives parallel their lives in the present as closely as possible -- a scientist traveling to ancient Rome might "become" a priest of Apollo, for instance. The longer they stay in the past, the more their "present" memories erode; the travelers must make a Will roll at an additional -1 every time they wake up to remember their true identities. (Characters with Temporal Inertia still have "new" lives, but suffer no memory erosion.) At the GM's discretion, this may produce Fright Checks or even mental disadvantages.

The Dead Past: The travelers arrive to find the past unchangeable. Perhaps time just doesn't advance while they're in the past, and they have to accomplish their mission during an eternal nanosecond. (This might actually make some missions -- like robbing the Louvre -- a lot easier!) Perhaps the travelers are only phantoms, unable to touch anyone or anything in the past. More subtly, they can never make any permanent impression on the past; people forget them right after talking to them, and anything they move returns to its original location when the travelers aren't looking.

Article publication date: February 25, 2005

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