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Infinite Worlds


Source Galaxy Exploration Manual pg. 92
Sucking marshes, desiccating deserts, frigid tundra, and crushing ocean depths may seem the height of inhospitable terrain to new explorers, yet such relatively mundane terrestrial biomes represent only a fraction of the galaxy’s impossibilities.
Nascent worlds rage with volcanic activity as their crusts cool, their semisolid surfaces ablaze with fresh lava. Rogue planets exiled by their exploding suns wander the lightless expanses. Aberrant lifeforms grow as large as planetoids, slumbering with unspoken aspirations as unsuspecting creatures carve out a life on their miles-thick carapace. Cosmic forces that could never support life in a mundane multiverse arise in arcane nebulae and star systems born from divine will. Across the galaxy’s billions of planets, the impossible becomes merely improbable, birthing biomes best described as weird.
In a science fantasy setting, weird biomes exist in part to provide a counterpoint to familiar Earth-like realms. What qualifies as weird may simply be a planet, star, or system encountered at an extreme point of its life cycle, such as newborn molten planetoids, realms so decrepit that they’re practically crumbling, or stubborn occult echoes of worlds that have long since disintegrated. More often, though, weirdness borrows from the outlandish tropes of planar travel, made even more jarring because weird biomes aren’t monolithic, infinite, divine realms; they exist within and are a natural extension of the Material Plane, reinforcing that the strangest destinations lie unsettlingly close to home. Unlike in mountains and deserts, adventurers can’t just turn on environmental protections to forget their surroundings; a weird biome presents a constant threat that could absorb, consume, or melt the complacent traveler. More than any other environ, these worlds aren’t just the setting; they’re the story itself.
Given their dangers, why hazard even approaching these worlds? In the case of living worlds, visitors might have no choice; these planets and colossal creatures often hunt down nearby starships, space stations, and whole worlds to consume or corrupt in the perpetuation of their million-year life cycles. Those who survive this predation often establish the beachheads for future exploration. What’s more, alighting on such a beast’s surface might be the only way for heroes to neutralize the behemoth and save their own homes.
More often, weird realms hide many of the setting’s greatest secrets: lifeless tracts preserve ancient knowledge for eons, tremendous living worlds are inimitable biological case studies, regions with aberrant physics might prove a critical testing ground for the next great technologies, and time-locked sanctums hypothetically exist where clues from the Gap survive into the modern era. In other cases, eccentric realms promise extraordinary resources. Intense pressures cause crushing atmospheres to rain diamonds. Magically warped nuclear fission yields supernatural elements key to building ever more powerful computers. Certain inorganic lifeforms might even photosynthesize raw UPBs, fulfilling that fanciful dream of money growing on trees. Through a combination of physics and magic, anything is possible, and each possibility is a scientific treasure, attracting unconventional adventurers with the promise of novelty and riches.

Weird Inhabitants

Source Galaxy Exploration Manual pg. 92
Where life exists in weird biomes, always consider how the creatures navigate, subsist, breath, reproduce, and survive. After all, even an utterly alien realm benefits from internal logic that makes its oddities more plausible. What’s more, these inhabitants might view PCs as the truly unnatural beings, establishing an unsettling dynamic for first-contact encounters.
Native species are often as strange as the terrain itself, and by necessity, such organisms have adapted to survive—and even thrive—under bizarre circumstances. Life in a volcanic expanse is likely virtually immune to heat, either naturally breathing the otherwise-toxic gases or being able to swap between different forms of respiration like aberrant lungfishes. Dead planets might lack true life, populated instead by undead or outsiders. Those dwelling on or within immense planet-beings must weather their host’s tremendous movements, with sustenance as likely to be parasitized from the planetoid’s body as captured through photosynthesis.
Inhabitants who originate offworld must have advanced technology, magic, or utter fortitude to survive, and they rarely settle these realms as a first choice. Instead, exile, desperation, or refuge drive immigration, and many of these creatures suffer in inhospitable surroundings that will never truly be home. Aucturn’s toxicity illustrates the trend, as any cultists and exiles who don’t choke in the toxic atmosphere inevitably mutate beyond recognition.
Most ominous of all are those creatures that can’t thrive in a weird biome’s current conditions—yet like seeds awaiting rain, these organisms can unfurl or hatch if the status quo changes, potentially creating an even stranger ecosystem!

Weird Adventurers

Source Galaxy Exploration Manual pg. 92
Player characters are exceptional, and no origin’s more exceptional than growing up on a weird world. These planets rarely appeal to mainstream residents, instead attracting an eclectic mix of the desperate, the academic, and the opportunistic—all shaped into rugged survivors by the experience. The “sea legs” of a child raised on an immense living creature’s surface give them extraordinary balance, represented by Acrobatics skill, and for those living worlds that can listen, learning the planet’s language and honing one’s Diplomacy can outright avert earthquakes. On volcanic worlds, freshly hardened rock formations can block paths, and a keen eye is critical to spotting solid ground, requiring capable Athletics, Perception, and Physical Science training. The weirder the world, the more likely magic is involved, and Mysticism is often more valuable than Life Science or Survival when navigating enchanted turf.

Weird Worlds

Source Galaxy Exploration Manual pg. 93
Weird biomes defy expectation; they tend to feel most natural when experienced in isolation, with an entire world being uniformly weird, rather than including an eccentric ecosystem on an otherwise mundane planet. Any monolithically weird world becomes a study in what-ifs. If a planet isn’t roughly spherical, how might that affect gravity? If a planet is truly dead, does it lack a magnetic field that would deflect cosmic rays? If a planet is largely molten, does it instead have an overwhelming electromagnetic field? For a living planet, does it need to feed or respire, and if so, how does that drive its weather? For utterly bizarre realms, does matter consist of completely alien elements or operate under aberrant physics?
Unpacking all the potential ramifications isn’t necessary when presenting a weird world; however, the GM should prepare at least three of these consequences as a way of illustrating the weirdness and making the world more believable. Thick skeletons could allow the native fauna to weather unexpectedly heavy gravity. Creatures on a dead world might shelter underground during the day to avoid irradiation, emerging at night to compete for ever-dwindling resources on the dying surface. Their counterparts on a molten world might be silicon-based or soar high above the lava, with visitors’ computer equipment malfunctioning almost immediately from overwhelming radiation. A living planet might exhale regularly, blasting air from crater-sized geysers that travelers exploit with sturdy gliders, reaching lofty ecosystems sustained by these updrafts.
Even where a world’s explanation is “it’s magic,” it needs an underlying logic. Identify and apply that logic consistently, and even the most bizarre planet can come alive—sometimes literally!

Weird Rules And Reference

Source Galaxy Exploration Manual pg. 93
Nearly anything can be true on a weird world, which affords a GM vast freedom in deciding which rules to apply from a vast array of possibilities. These planets might be utterly hostile to life, in which case abnormal atmospheres are ideal—anything from the corrosive, toxic, and strange atmospheres on pages 395–396 of the Core Rulebook to no atmosphere at all. Erratic orbits, rapid rotation, and worse could beget extreme weather, using the rules on pages 398–400 as a starting point. Gravity (pages 401–402) could range from extreme to erratic, applying inconsistently across some worlds. Even terrestrial worlds, partly warmed by radioactive decay in their cores, might weep radiation (pages 403–404) across whole continents. For those worlds where physics simply doesn’t work as expected, the physical and mental disease tracks (pages 414–415) can represent explorers’ gradual degradation. Most crucially, remember that weird worlds are exactly that: weird. If ever there’s a time to apply strange circumstances, modify existing rules, or invent your own, this is it.

Weird Toolbox

Source Galaxy Exploration Manual pg. 94
See Biome Subsections on page 46 for advice on how to use the following tables.

Weird Inhabitants

5–8AstrazoanCloud ray
9–12Bodysnatcher slimeColour out of space
13–16Bone trooperDeh-nolo
17–20BoraisDemon, pluprex
25–28Cerebric fungusDinosaur, radioactive
29–32ContemplativeFrujai colony
33–36CopaxiGlass serpent
37–40CorpsefolkHerd animal, thermic
45–48Dragon, voidIrokiroi
49–52Entu colonyMagma ooze
53–56Genie, efreetiMi-go
61–64HanakanPlague ooze
65–68HortusProtean, rifti
69–72HulsaPsychic abomination
73–76JinsulQuantum slime
77–80Kami, chinjugamiRobot, mining
81–84Oracle of OrasThermatrod
85–88OrocoranThermophilic ooze
89–92QuorluTroll, void
93–96ShirrenUndead minion
97–100UrogVermin, necropede

Weird Adventure Hooks

D20Adventure Hook
1 Centuries-long volcanic eruptions cease in the course of a single day, and lava worldwide begins to drain back underground in a deafening torrent. Where is all of this molten rock going, and what subterranean realms is it uncovering in its wake?
2 A dead zone blasted to lifelessness millennia ago unexpectedly hides stasis pods or dormant eggs, the last vestiges of a forgotten past. Biologists’ excitement fades to panic when these lifeforms awaken, enraged by their barren environs and intent on destroying all other life.
3 Ghost-haunted ruins have continuously replayed millennia-old, pre-Gap scenes, yet recently, the ghosts began speaking of their experiences with the Drift as if the plane existed in their time.
4 With little warning, tectonic plates have taken flight like spacefaring manta rays, carrying continents on their backs and leaving behind a molten core. Where is this convoy of immense aliens traveling, and what is the fate of those stuck on their backs?
5 An inverted planet, with a molten exterior and a hollow, inhabitable interior, cracks open once every 96 years, allowing traffic for several weeks before closing. The planet has just reopened. What lies within?
6 After disgorging lava for eons, several volcanoes have run dry. Passageways lead deep into the planet’s core, where cooling caverns bear prophetic inscriptions in Ignan warning of an apocalypse “when the halls grow cold.”
7 Slain in an ancient age, an amorphous planet is actually the curled corpse of a dead god. Literal veins of precious metals have long attracted prospectors, yet recent pilgrims have developed inexplicable spellcasting powers. Is the god coming back to life?
8 Tens of thousands of miles long, an immense angler fish beast swims through space, its glowing lure heating its back like a miniature sun. The people living atop its back recently learned how to steer the beast, urging it to gobble up planets in their quest for resources.
9 Rather than seasons, a rocky world experiences phases where rifts open to particular planes. The season of Maelstrom dawns, and the planet seems to be mutating as proteans swarm the surface.
10 Seven planets, each carefully carved with miles-wide runes, orbit a star with clockwork precision. Astronomers predict that all seven will align perfectly later this year, but it’s unclear whether this event might open a portal, trigger a miracle, or something stranger.
11 Five titanic, insectile limbs project from a planet, each bursting through at the beginning of a new age. A deafening tapping has begun under one continent. Is a sixth leg approaching, and does this mean the planet might fully hatch at long last?
12 Nearly a third of a moon’s mass consists of vast servers, processors, and other computers, all whirring busily while tended by robotic minions. It’s clear the moon is calculating something, and more ominously, a large display appears to be counting down to an imminent date.
13 A nearby star emits trace amounts of siccatite, which has accumulated in thick layers on an orbiting world over billions of years. Corporations now clash on the planet’s pyro-taiga to control the mineral rights.
14 The souls of those who die in this biome become comfortable ghosts, never judged by Pharasma. Psychopomp starships patrol the skies to fend off scoundrels who would die here rather than languish in Abaddon. The PCs must brave the blockade to question a dead murderer’s spirit.
15 Flung from its sun eons ago, a rogue planet’s frigid surface encases millions of undead inhabitants. As the planet approaches a new star system, the ice thaws, releasing the undead to pillage nearby worlds.
16 An aberrant world abducts anyone in the galaxy who dreams of its haunted surface. A mysterious holovid circulates widely, showing these landscapes to the unwary, who wake from terrible nightmares to find themselves trapped untold light years from home.
17 Paleontologists uncover countless layers of mass extinctions that occurred like clockwork on a vibrant world, and the evidence suggests another die-off is imminent. They’re desperate to uncover what keeps killing off all life before this unique ecosystem is lost forever.
18 A barely sentient expanse of the Abyss manifested on the Material Plane during the Gap, only to be settled by skittermanders who adore the living planetoid, confusing and calming its demonic instincts. A recent raid by off-worlders has riled the planetoid, threatening its residents and nearby worlds alike.
19 Haunting dreams plague anyone who alights on a lifeless planet, causing visitors to transform into the planet’s long-dead, once-dominant species. Exceptionally strong and smart, they’re operating from a gutted metropolis, hoping to abduct and transform more victims.
20 An immense ring world surrounds a mystic portal through which nothing has ever returned, including those rim inhabitants with fatal curiosity. Suddenly, an explorer missing for millennia emerges from the portal, carrying tales of untold riches and a growing threat on the other side.