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Hazards can be either extra-vehicular, that is, something starships encounter in space, or can be inter-personal. That is, things PCs encounter personally.

Personal Hazards

Personal hazards are challenges that PCs must overcome that do not involve space travel, or rather, are challenges which the PCs face more directly, like decompression hazards, or exploding airlocks. Detailed below are some examples.

Decompression Hazard CR 1

Source SAP26

XP 400
Type analog; Notice Perception Engineering DC 16 (interpret warning lights are for an airlock with vacuum on the other side); Disable Engineering DC 16 (close the door despite air pressure)
Trigger location (opening the door); Reset each round the door remains open and unobstructed and when the iris door closes.
Effect multiple targets; target closest to door pulled into opening (1d6 B and grabbed [DC 16 to escape; 1d6 B each round the target fails to escape and the target is unable to breathe]); other targets pulled up and slammed against the ceiling (1d4 B) and if the target closest to the door is pulled in (1d6 B); Reflex DC 12 negates either effect, as does being secured or holding onto an immovable object. Those able to move while the hazard is active can do so only at half speed.

Electrified Containment Door CR 3

Source SAP26

XP 800
Type technological; Perception DC 24; Disable Engineering DC 19 (disable the control panel in 2d4 rounds)
Trigger touch; Reset immediate; Bypass security hand sign given to camera near the door (Computers DC 19 to hack as 1 full action)
Effect electrical discharge (6d6 E); Reflex DC 14 half

Decontamination Jets CR 2

Source SAP26

XP 600
Type technological; Perception DC 23; Disable Engineering DC 18 (take 1 minute to disable process while one door is open) or Engineering DC 12 (disable one of five ceiling nozzles as a standard action)
Trigger both doors shut; Reset 5 rounds and either door opens; Bypass reconfigure spray to aim at walls (Computers DC 18 to hack as 1 full action)
Effect jet spray (1 B and knocked prone); Fortitude DC 12 negates; multiple targets; each nozzle disabled reduces the DC by 1

Experimental Vracinea Blooms CR 2

Source SAP26

XP 600
Type analog; Perception automatic; Disable kill the blooms EAC 11; KAC 11; HP 2 per bloom (13 blooms); Fort +2; Ref automatic failure; Will as an object; immune to mind-affecting effects; Trigger proximity (visual); Reset immediate; Effect Any living creature within 120 feet of the blooms and able to see them finds them alluring and must succeed at a DC 13 Will save at the start of its turn or the creature must use 2 move actions each round to move toward the blooms at full speed. The creature must maintain line of sight to the blooms as it moves. An affected creature within 5 feet of a bloom becomes fascinated by it. Once a creature saves against this effect, it is immune to this hazard’s alluring ability for 24 hours. This is a mind-affecting, sense-dependent (visual) effect. A living creature that enters or starts its turn within 15 feet of a bloom must succeed at a DC 13 Fortitude saving throw or become paralyzed for 1 round. Once a creature saves against this effect, it is immune to this hazard’s paralyzing ability for 24 hours. This is an inhaled poison effect.

Laser Defense Grid CR 3

Source SAP26

XP 800
Type technological; Perception DC 24 (spot the six ceiling hatches for the lasers); Disable Computers DC 27 (bypass firewall) and Computers DC 25 (shut the grid down), or Engineering DC 16 (disable one laser)
Trigger touch (failed hacking attempt); Init +8; Reset immediate; Bypass counter start-of-round confirmation order (Computers DC 19 or Bluff DC 19, as a reaction)
Effect laser +9 ranged (1d4 F); up to six targets (can target one creature more than once)

Space Hazards

While some believe that space is an empty void, there are many hazards that can affect space travel, either to the benefit or to the detriment of a spacefaring vessel and its crew. Most environmental hazards in space can be avoided, but not all, and when moving through the Void or hyperspace, unless the route is known and the vessel’s pilot is prepared, vessels may randomly stumble across an environmental hazard that could put their journey, their vessel, and their crew at risk.

Random Space Hazard Encounters

Hazards may be encountered randomly or simply at the GM’s discretion. Should the GM wish to use the random encounter tables listed below, they are provided for that use. These encounters typically occur randomly while in hyperspace as determined by the GM.

If a field is encountered, a separate table is included to determine the overall size of the field.

Table: Random Hazards
d% Hazard Type
01-64 Open space (nothing)
65 Antimagic Field
66-69 Asteroid Field
70 Comet
71-74 Dust Cloud
75-77 Ice Field
78-79 Magnetic Field/Storm
80-82 Meteor Shower
83-85 Nebula
86-88 Radiation Belt
89 Ribbon Storm
90-92 Slipstream
93-95 Solar Flare/Wind
96-97 Wormhole
98-99 Roll Twice (ignore this result if rolled again)
100 Roll Three Times (ignore this result if rolled again)
Table: Cloud/Field Magnitudes
Magnitude1 Encounter Chance (%) Diameter (in Cubes) Size Modifier
Tiny 01-44 1 -2
Small 45-64 8 -1
Medium 65-74 27 +0
Large 75-84 64 +1
Huge 85-92 125 +2
Gargantuan 93-99 216 +4
Colossal 100 343 +8

1: Clouds and Fields in space do not have equivalent magnitudes for diminutive or fine.

Hazard Examples

Asteroid Field/Meteor Shower

Asteroid fields are largely stationary groupings of rocks and ores that float about in space. They are divided into two primary classifications; passive and active. Passive asteroid fields are older, more stable fields that often are arranged into asteroid belts (though not exclusively so), and there is very little movement among the asteroids. This is not to say that they do not present a danger, but active fields are far more deadly. Active asteroid fields are those where the asteroids are randomly moving rapidly throughout the field, smashing against one another and crushing anything unfortunate enough to be caught within their boundaries.

Meteor showers are much like active asteroid fields, but the rocks are traveling in a specific direction. Meteor showers can sweep across space lanes, or can even shower down upon planets. Fortunately, most of the stones in a meteor shower burn up in the upper atmosphere of a planet, but those that get through often cause great devastation.

Asteroid fields or meteor showers that occupy hexes of space between or surrounding vessels in combat, grant concealment to such vessels, but do not prevent line of sight.

The following table determines the amount of damage per round done to any vessel caught within an asteroid field or meteor shower.


Comets are colossal chunks of frozen gases, liquids, and rock that are hurtling through the void at incredible velocity. They throw off a long tail of melting gas and rock particles that can be seen stretching out behind it for tens of miles. While the odds of striking or being struck by a comet are incredibly remote, comets are usually harbingers of other dangers than just ice and rock. Strange creatures often accompany, or follow behind comets, and pirates or invasion forces often follow the trail of comets as they streak through the universe, for many cultures see comets as messengers of the void gods and blindly follow them through the void.

The tail of the average comet is only a single hex across and eight hexes long, though some comets are so large that their tails are up to eight hexes across and 50 hexes long. If a vessel flies through the tail of a comet, the damage is equivalent to that of an active asteroid field.

Comets often carry a wealth of valuable resources trapped within, and therefore, some adventurers and merchant guilds attempt to capture comets, or even mine them as they travel. Such work is incredibly dangerous, and many who attempt these acts do not survive, but the rewards are well worth the risks; most comets carry enough valuable ores and minerals to purchase a large city.

Corrosive Cloud

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

This naturally occurring cloud drifts silently through space,eating away at objects that it comes into contact with.The particles of a corrosive cloud, millions of microscopic grains comprised of thousands of different radioactive and acidic molecules, are highly destructive, capable of eating away through the thickest armor found on starships.

A corrosive cloud, typically colossal in size, moves at a speed (in hexes) of 5 in a constant direction, dealing 4d20 points of damage each round to anything that it comes into contact with. If a corrosive cloud comes into contact with the atmosphere of a planetary body there is a 95%chance that the cloud will be completely consumed in the planet’s atmosphere. If a cloud is not destroyed in this manner may meld with organic matter on the planet’s surface, forming a corrosive membrane.

Corrosive Membrane

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

These long, flesh-like strings stretch across objects, slowly growing to fill entire areas if they’re left unchecked. A patch of corrosive membrane springs from the shell of a character or creature that was completely devoured by a patch of corrosive membrane.

This foul hazard has a symbiotic relationship with slimy doom: a corrosive membrane patch shrivels up and dies within 2d6 minutes of being separated from a patch of corrosive membrane. A single 5-foot corrosive membrane patch deals 1d2 points of Constitution damage per round (+1 point of Constitution drain for each adjacent corrosive membrane patch) while it devours flesh.

Against wood or metal, a corrosive membrane patch deals 1d3 points of damage per round, ignoring metal’s hardness but not that of wood. It does not harm stone. 5 or more points of cold or fire damage destroys a 5-foot corrosive membrane patch.

Cybernetic Slime

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

This black-colored slime is a mixture of artificial and organic fluids, brought into existence when a cybernetic component is damaged and left unrepaired.

One week after suffering damage, there is a 20% chance that an unrepaired cybernetic component will fill with cybernetic slime, inflicting 1 point of Constitution damage to the character for each day the problem is left untreated.

A character that is completely consumed by the cybernetic slimes (and character reduced to a Constitution score of 0 or lower) is forever lost, leaving behind a 5-foot patch of cybernetic slime. Curing a character of cybernetic slime – before it kills him – requires that the damaged cybernetic component be repaired and then five successful Treat Disease checks (DC 15), each check requiring a full day during which time the victim may do nothing but rest.

When touched, a 5-foot patch of cybernetic slime deals 2d4 points of acid damage per round while it devours flesh. On the first round of contact, the slime can be scraped off a creature (most likely destroying the scraping device), but after that it must be frozen, burned, or cut away (dealing damage to the victim as well). Against wood or metal, cybernetic slime deals 1d6 points of acid damage per round, ignoring the metal or wood’s hardness.

A character with cybernetics that comes into contact with a patch of cybernetic slime must make a successful Fortitude saving throw (DC 15) or the character is Stunned”>stunned for 2d4 rounds, during which time the slime devours the character’s flesh.

A patch of cybernetic slime is destroyed if it suffers 10 points of fire or electricity damage in a single attack.

Dark Matter Cloud

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

Undetectable and rare, a cloud of dark matter, a type of matter that can only be seen with advanced equipment, though it’s effects on gravity can be detected as can have devastating effects on any starship unfortunate enough to cross paths with this hazard. Dark matter clouds float seemingly aimlessly through space, rarely a concern for starships or their crews.

When a starship comes into contact with a dark matter cloud – most clouds are medium size though a few reports of larger clouds have been recorded in the past – the ship immediately suffers 4d20 points of damage as the dark matter particles come into contact with the ship’s hull.

After suffering damage, the pilot must make a successful Pilot check (DC 20) when leaving the affected tactical hex – on a failed check the ship suffers another 4d20 points of damage as it pulls away from the cloud.

A starship equipped with basic medium-range sensors or greater making an active sensor scan over an area of space affected by a dark matter cloud can correctly locate the cloud’s position on a successful check (DC 30).Once detected by sensors the starship can track the clouds position for 3d4 rounds after which point the cloud must be reacquired.

Deep Space Wave

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

Similar to cosmic rays, a deep space wave is a stream of molecule-sized particles moving rapidly through space – the source of deep space waves has yet to be discovered.When a deep space wave impacts a starship the particles rip through the ship’s hull, creating millions of molecular holes that breach the starship’s hull.

A starship equipped with sensors that makes an active sensor scan over an area of space affected by a deep space wave can correctly locate the wave’s position on a successful check (DC 20). Unprotected characters and creatures that are exposed to radiation from a deep space wave shower are treated as “moderately irradiated” for the purposes of determining the radiation’s effects (see Radiation Sickness).

Drift Storm

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

A drift storm is an unusual galactic disturbance in which the bending of light and space plays havoc on starship’s drift technology systems and personnel traveling through drift space. When a drift technology is activated there is a 2% chance that a jump storm will erupt, affecting all starships that travel through this particular route – if established drift lanes are used in the campaign – for the next 2d4 hours.

During a drift storm the affected starship is helpless for the duration of the trip and emerges into real space where it remains helpless for 3d6 rounds. As long as the starship is helpless all crew members are Stunned”>stunned.

Dust Cloud

Cosmic dust is generally harmless, but it does obscure vision, as it reflects visible light, and if a vessel passes through it, it is coated in the dust particles until it is fully scrubbed clean; a process that can take days, depending upon the size of the vessel. While coated in cosmic dust, cloaked vessels no longer have an additional +8 AC bonus but they keep their immunity to TL. It may be a minor hazard, but it can be tactically effective.

Dust clouds that occupy hexes of space between, or surrounding, vessels in combat grant concealment to such vessels, but do not prevent line of sight.

EMP Field

There are zones, or bubbles, of electromagnetic radiation that float out in the depths of the void, trapping unsuspecting vessels that rely upon technology for their propulsion and preventing the usage of any and all technological items. While some are marked on star charts, others are either stumbled upon randomly, or can be marked by the presence of derelict vessels floating nearby. Scavengers and pirates are often wary of such “vessel graveyards”, as they may indicate the presence of nearby EMP fields.

EMP fields generally come in spherical form, and in order to escape from an EMP field, one can either hope to drift out of it, or by using some magical means of escape. There is no way of predicting how large an EMP field may be until it is fully explored. EMP fields do not have a tendency to drift or move in space, though certain astronomical events can shift their position.

Vessels that enter an EMP field under technological propulsion immediately stop accelerating and become incapable of changing direction. Trapped vehicles begin to decelerate due to microgravity within the EMP field at a rate of 1 Speed per round (minimum of 1 Speed), whereupon they drift in a random direction each round upon achieving Speed 1. Unwary travelers that do not have magical means of escape can remain stuck in EMP fields for so long that they either die of asphyxiation, dehydration, or starvation, depending on their reserves.

Table: Asteroid Fields &Amp; Meteor Showers
Asteroid Field (Passive) d% Asteroid Field (Active) d% Meteor shower d% Asteroid/Meteor Size Collision Damage (in VP) Profession (pilot) DC to avoid1
01-20 01-10 01-05 None
21-40 11-25 06-15 Diminutive 1d4 35
41-45 26-40 16-32 Tiny 1d6 32
46-59 41-55 33-52 Small 1d8 30
60-74 56-70 53-72 Medium 2d6 27
75-84 71-80 73-87 Large 3d6 25
85-91 81-90 88-95 Huge 4d6 22
92-97 91-95 96-98 Gargantuan 6d6 20
98-100 96-100 99-100 Colossal 8d6 15

1: Avoiding asteroids in an active asteroid field is far more difficult than avoiding asteroids in a passive field. Active asteroid fields add a cumulative +2 to the DC to avoid asteroids in consecutive rounds.

Endothermic Mold

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

Endothermic mold feeds on warmth, siphoning heat from anything around it. A patch of endothermic mold is red-brown in color and 5 feet in diameter, and the temperature is always cold in a 30-foot radius around it. Living creatures within 5 feet take 3d6 points of nonlethal cold damage. Fire brought within 5 feet of the mold causes it to instantly double in size.

A 5-foot patch of endothermic mold is destroyed if it takes 5 or more points of cold damage.

Gene Mold

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

This dull gray-green mold is sometimes created when a tank holding a genetic experiment – usually in a thick, liquid-like substance – is cracked and the genetic material leaks, pooling on the ground beneath the tank. If left alone for 1d6+1 days the substance begins to grow, forming a 5-foot square patch of genetic mold. If disturbed by any means (touch, wind, etc.), a patch of genetic mold releases a cloud of spores that are toxic to any character or creature that the spores come into contact with. All characters and creatures within 10 ft. of the mold must make a Reflex save (DC 20) or be subjected to Gene Fever. Fire destroys a patch of gene mold.

Gravitational Fog

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

This harmless looking cloud of fog, a dull gray in color, hangs suspended a few feet above the ground. Encountered only on small planets and large moons with a toxic atmosphere, a gravitational fog is a bizarre gravitational anomaly – the fog adjusts the world’s gravity (if it is normal) by one step in a random direction (determine once for each fog encountered) in the squares it covers and those adjacent to it. On a low- or high-gravity world the fog shifts the affected area’s gravity to normal.

A gravitational fog cannot be dissipated – high winds, artificial or natural, have no effect on the fog. The only thing that can be done is to wait for the fog to cease to exist on its own; a gravitational fog patch – most are a 20-foot cube – has a natural lifespan of only 4d6 hours.

Ice Field

Ice fields can be just as deadly as meteor showers or asteroid fields, and can be just as harmful. As asteroid fields do, ice fields come in active and passive formats, and cause the same degree of damage, though half of that damage is bludgeoning damage and the other half results directly from the extreme cold of the ice.

Vessels sometimes play cat and mouse games within ice fields, despite the dangers. When vessels engage in combat within an ice field, all vessels only have a 25% chance of being hit by an attack each time they are targeted.

Ice fields that occupy hexes of space between, or surrounding, vessels in combat grant cover to such vessels, but do not prevent line of sight.

Magnetic Field/storm

Magnetic fields are stationary zones of incredibly powerful magnetic energies, while magnetic storms are similar zones that are mobile. Either type can cause major disruptions to purely technological systems and are best avoided if at all possible. When vessels pass through a magnetic field or storm, technological systems and objects take 5d6 HP of damage for each round that they are exposed to the effect. Objects made of iron or steel automatically adhere to the largest of such objects (which can include walls, floors or ceilings) and require a DC (15 + the magnetic field’s size modifier) Strength check to pry apart.

Vessels made of iron or steel are drawn together at the rate of 1 hexes per round, and multiple vessels can become magnetized together, effectively occupying the same square until they pass through the effect. Vessels that collide as a result of being magnetized together take 6d6 HP of damage for each vessel they collide with. Separating magnetized vessels requires a DC (20 + the magnetic field’s size modifier) Piloting check, provided that there is open space to move the vessel away.

Magnetic Slime

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

This dark black slime disrupts electrical and computerized devices within its sphere of influence and eats away at anything that it comes into contact with. Wet and sticky, the slime clings to walls, ceilings, and floors in patches. The slime drops from the walls and ceilings when it detects nearby electrical or computer activity. When possible the slime draws energy from electrical and computerized devices, using the energy to expand in size – for every individual electrical or computerized device destroyed by a patch of magnetic slime the patch grows by 1-foot.

A single 5-foot square of magnetic slime disrupts all electrical and computerized devices in its own square and adjacent squares. If the slime comes into contact with an electrical or computerized device there is a 20% chance that the device will be completely destroyed (+10% each additional round that the slime remains in contact with the device).Additionally, magnetic slime is slightly corrosive, dealing 1d4 points of damage to any character, creature, or object for each round of contact. On the first round of contact, the slime can be scraped off (most likely destroying the scraping device),but after that it must be frozen, burned, or cut away (dealing damage to the object or victim as well). Any cold or fire damage destroys a 5-foot patch of magnetic slime.


Nebulae are largely stationary clouds of ionized, anti-magical gases that not only obscure vision, but can cause a multitude of vessel systems to temporarily malfunction. Defensive components (other than armor plating) and tactical systems fail to function within a nebula, as do teleportation devices and spells. Vision is obscured beyond a single hex, and Speeds are capped to a Speed 5. As nebulae can greatly interfere with a vessel’s ability to defend itself from attack, only the most damaged and desperate of vessels deliberately fly into a nebula in combat situations.

Nebulae that occupy hexes of space between, or surrounding, vessels in combat grant concealment to such vessels. However, vessels within a nebula do not have line of sight to vessels outside of the nebula, and vice versa, nor do vessels that have a nebula positioned between them.

Oort Cloud

Oort clouds exist in the vast pockets of void in interstellar space, and are impossible to avoid. They are comprised of frozen packets of water, ammonia and methane gases; are the spawning grounds of comets; and exert vast gravitational pressures upon the void in similar fashion to ocean tides.

For each 5 hexes that a vessel travels through an Oort cloud, they suffer a cumulative 5% chance of being “blown off course”, effectively doubling the number of hexes of the vessel must travel to get through the Oort cloud. Vessels using a phase box as their active engine are immune to this tidal effect.

Within an Oort cloud, all damage from cold-based environmental hazards such as comets or ice fields is doubled, as is any radiation damage regardless of its source. However, due to the incredibly high concentration of ammonia in an Oort cloud, acid damage from environmental hazards or attacks upon a spacefaring vessel is halved.

Lastly, it is incredibly dangerous to work on the outer hull of a vessel within an Oort cloud. Creatures on the outside of a vessel’s hull must make a DC 30 Athletics check as a swift action each round or be swept off of the vessel and carried out into the void.

Oort clouds that occupy hexes of space between, or surrounding, vessels in combat grant improved cover to such vessels. However, vessels within an Oort cloud do not have line of sight to vessels outside of the Oort cloud, and vice versa, nor do vessels that have an Oort cloud positioned between them.

Orbital Swarm

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

Around once-technologically advanced planets that have experienced an apocalyptic event, leaving them reduced to the Stone Age, there is frequently a debris field littered with long-forgotten, malfunctioning satellites, spacecraft, and orbital stations. As the centuries pass, much of this debris falls to the planets surface and is destroyed. Sometimes, though, gravitational and galactic forces act in unexpected ways to create a dense swarm of debris that continuously orbits the planet, hampering any attempts to enter or escape the planet’s atmosphere.

A world surrounded by an orbital swarm requires six Pilot checks (DC 25) anytime a starship enters or exits the planet’s atmosphere. On each successful check the starship suffers 2d8 points of damage from debris; on each failed check the starship suffers 2d20 points of damage.

Planetary Ring

While not every planet has them, planetary rings are very similar to asteroid belts. They are typically passive in nature, and some are made entirely out of ice, dust, or gases instead of rocks. In fact, most planets that possess ring systems have rings that are made out of a combination of materials.

Planetary rings form in a variety of ways; often either by the debris of moons that were impacted by some large object, the debris of moons that were ripped apart by their planet’s gravitational forces, or potentially even the collection of dust clouds that drifted too close to a planet’s orbit.

Table: Planetary Rings
Size Classification Width (in hexes) Depth (in hexes)
Vermin 1-4 1
Familiar 5-11 2
Stirge 12-20 3
Fey 21-31 4
Humanoid 32-45 5
Chimera 46-62 6
Hydra 63-81 7
Kraken 82-103 9
Dragon 104+ 10

Regardless of the reason for the formation of a planetary ring, they are treated as if they had the qualities of all of the environmental hazards that are similar in their makeup: if rocks are present, treat them as a passive asteroid field. If they contain ice, treat them as if they were an ice field. If dust is part of their makeup, treat them as if they were a dust cloud. If they are made up, even in part, by gases, treat them as if they were a nebula.

Planetary rings can grow to nearly any size. See a planet’s size classification to determine the size of the planetary ring.

Radiation Belt

Radiation belts are swaths of radiation floating out in the void. Vessels that pass through radiation belts are unharmed, but their crews suffer the effects of radiation for as long as they remain within the irradiated areas.

Radio Echo

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

Space, especially regions close to inhabited worlds, is overrun with radio echoes from the past. In some instances starships stumble across areas of space in which intense radio echoes have near-catastrophic effect on the starship’s sensors and communications gear. A typical radio echo is a Line“>line of disruption 10,000 ft. wide that stretches completely through a star system – any starship that passes through this Line“>line of disruption suffers the adverse effects of the radio echoes.

A starship’s sensors are reduced by 5 hexes when inside a radio echo stream. If this reduces the sensor’s category below 1 hex, the ship effectively has no sensors until it leaves the affected area of space.

Starship communications systems are completely worthless when the ship enters a radio echo stream. This includes the starship’s internal communications systems.

Radio echoes can be detected with a standard active sensor.

When encountered the starship’s communications system is filled with thousands of communications from the past, all of which are overlapping each other making it impossible to understand anything received by the ship’s communications systems.

Ribbon Storm

Ribbon storms are one of the deadliest and most insidious hazards of space travel. A ribbon storm is comprised of foot-long hyper-virulent fungal filaments capable of eating through most anything they come into contact with using hyper-corrosive acids. As each fungal filament, or ribbon, feeds, it grows in size, reaching lengths of ten feet and swelling to a foot in diameter. Full grown ribbons die within minutes. These ribbons only devour what they come into contact with; on their own, they do not move or attack nearby beings. They have no muscular system, being comprised of tightly wound strands of fiber, nor do they have anything resembling a nervous system. They merely excrete powerful acids and the outer surface absorbs the resulting slurry.

Ribbon storms are high-density fields of floating ribbons that travel through space, often in the wake of a comet, asteroid, or vessel. When ribbon storms are encountered in deep space, they are often left there as a result of falling too far behind whatever was dragging them along.

Occasionally, ribbon storms are brought into contact with a planetary body, and although most ribbons burn up in the atmosphere, more than enough survive to make landfall, eagerly devouring all matter they come into contact with.

No one quite knows where ribbons come from, but it is known that they reproduce asexually, breaking off into smaller segments which grow into filaments that are ready to feed.

Traveling through a ribbon cloud causes 1d6 HP of damage per round to any vessels caught within the storm. Ribbons that touch living creatures or constructs that are not immune to their acids inflict 10d6 damage per round that they remain in contact.

A ribbon is particularly vulnerable to fire, burning up completely on contact. It also drowns in water within 1 round, its acids dissipating harmlessly.

Ribbon storms that occupy hexes of space between, or surrounding, vessels in combat grant soft cover to such vessels, but do not prevent line of sight.


Slipstreams are invisible rivers of force that drag vessels along in their wake. While they are largely undetectable, there are quite a few slipstreams that are marked on star charts. They rarely travel through a solar system, but they often travel near enough to them that they are regularly used as “space lanes” for traders, adventurers, and pirates.

Slipstreams can be dangerous to cross; traveling across a slipstream exerts extreme gravitational forces upon the vessels that cross them. However, traveling along with the slipstream is expeditious. Vessels plot their course along the slipstream’s path and merge together with it seamlessly (taking no damage).

A slipstream’s force is determined by its size; lesser, standard, or greater. Consult the chart below to determine a slipstream’s Speed and force.3

Table: Slipstreams
Slipstream Type Slipstream Diameter Force Damage per round (in VP)1 Speed Boost
Lesser 4 Cubes 4d8 +3 Speed
Standard 8 Cubes 6d8 +5 Speed
Greater 16 Cubes 8d8 +10 Speed

1: Force damage is only inflicted if a vessel is crossing or traveling against the flow of the slipstream.

Solar Flare/wind

Solar phenomenon only occur within solar systems, but their effects can be quite powerful. Solar flares can lash out from any type of star to a distance of thousands of miles, while solar winds are charged particles that are flung outward from stars. Each can have devastating effects upon vessels that pass through them.

Solar winds can knock vessels off course. Unless the vessel is propelled by magic, passing through a solar wind pushes a vessel 1d6+1 hexes per round in the direction that the solar wind is traveling. Some vessels use solar winds to help propel them faster, riding the solar wind toward the outermost planets of the system.

Solar flares are another matter entirely. Vessels caught within the blast of a solar flare can take a punishing amount of fire and heat damage, and many do not survive. Even the heaviest of spacefaring vessels take critical damage from being caught within a solar flare, unless they are protected from fire damage.

Solar winds use the same size chart for cloud or field hazards to determine their size. Solar flares use this chart below to determine their size and how much damage they do.

Solar Flares
Star Type Flare Size (x10 Cubes) Flare Diameter (in Cubes) Flare Damage (in VP)
Blue Star 6d12+9 17 4d20+50
Blue-White Star 4d8+7 15 2d20+40
Brown Dwarf
Orange Star 2d4+1 8 2d8+20
Red Star 1d6+1 8 2d6+10
Red Supergiant 1d6+1 8 2d6+15
White Dwarf 2d8+5 13 3d8+30
White-Blue Star 2d8+5 13 2d20+30
Yellow Star 2d4+3 10 2d4+25

Solar Storm

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

A solar storm is an usually powerful form of solar flare that functions exactly like a solar flare except the Fortitude save DC to resist the radioactive effects of the storm is increased to 30. Starships caught in a solar storm have a 20% chance of suffering computer and electrical systems failure. If this happens the ship is rendered helpless until the systems can be repaired (requiring a successful Engineering check (DC 15 + 1 for every minute the ship remains in the solar storm, making these repairs requires three hours).The chance of suffering computer and electrical systems failure increases by 5% for each round the ship remains within the storm.

Temporal Fog

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

This thick, black cloud rolls slowly across the landscape of alien worlds that have been subjected to a barrage of devastating temporal anomalies. On some worlds that have seen thousands of temporal gateways – either natural or man-made – temporal fog can grow to cover miles of area at once. Fortunately for most, though, a typical patch of temporal fog appears as a 20-ft.cube. Any character or creature entering a temporal fog is negatively affected,the fog instantly advancing their age by 2d4 years (a successful Will save [DC 15] reduces this time to 1d4 years). This adverse effect on the character or creature’s age happens each time that the fog is entered.

A patch of temporal fog moves at a rate of 20 ft. – in a random direction – and cannot be dissipated. The only thing that can be done is to wait for the fog to cease to exist on its own; a temporal fog patch has a natural lifespan of 1-2 hours per 5-foot square that it covers. There have been reports of temporal fogs that act as gateways in time, opening a portal to either a time in the distant past or the distant future. Such fogs still negatively affect the age of anyone that enters them.


Creatures exposed to a vacuum cannot breathe and immediately begin to suffocate. The rules below offer optional expansions to those rules, which might be especially useful if running a campaign in a lower technology area or involving creatures unused to navigating the vacuum of space or an airless planetoid.

Slow Suffocation: A Medium character can breathe easily for 6 hours in a sealed chamber measuring 10 feet on a side. After that time, the character takes 1d6 points of nonlethal damage every 15 minutes. Each additional Medium character or significant fire source (a torch, for example) proportionally reduces the time the air will last. Once rendered unconscious through the accumulation of nonlethal damage, the character begins to take lethal damage at the same rate.

Small characters consume half as much air as Medium characters. If the sealed chamber, such as a spacecraft or habitat module of a damaged moon base, you must determine the speed at which air is escaping, decreasing how long characters can survive by a proportional amount.

Spellcasting in a Vacuum: Vacuum presents particular difficulties to spellcasters that need to breathe, requiring a successful concentration check (DC 15 + spell level) to avoid losing the spell. In addition, a spellcaster using verbal components cannot hold their breath to avoid suffocation and must use the breath they were holding to cast the spell. Casting a spell as a standard action reduces the caster’s remaining breath to 0 rounds, while casting a spell as a swift action leaves her with 1d6 rounds of breath remaining. Spells with casting time of 1 round or longer cannot be cast in a vacuum by a caster that needs to breathe.

Creatures that do not need to breathe need not make this check and do not expend additional breath by casting spells, though taking any standard or full-round action consumes 1 additional round of breath as normal.

Fire Effects: Spells that create fire are especially difficult to use in a vacuum, requiring a separate concentration check (DC 20 + spell level) to successfully cast, creating a momentary surge of heat that lasts long enough to deal damage and otherwise create effects with an instantaneous duration but then dissipates. Even then, such effects are weakened and grant a +2 circumstance bonus on saving throws. Supernatural fire effects are ineffective in a vacuum unless the character creating them succeeds on a DC 20 level check.

Specific abilities may obviate this requirement, and creatures native to space (such as outer dragons) may use supernatural fire effects without difficulty at the GM’s discretion.

Gases: Gases, vapors, mist, and the like dissipate quickly in a vacuum, with their duration reduced by one step in the following order: 1 hour/level, 10 minutes/level, 1 minute/level, 1 round/level.

Effects that normally persist for only 1 round/level have their duration reduced by 50%.

Preparing Spells in Space: Lacking common reference points for timekeeping such as an ordinary passage of day and night, spellcasters in space (especially if not native to an extraterrestrial environment) may have trouble timing their preparation of spells. You may allow PCs to prepare spells without difficulty, but if you wish to enforce a period of learning how to study the rhythms of space you may require some form of magical or mechanical timekeeping device.

Sonic Effects: Sonic effects are equally as difficult to use in a vacuum as fire effects, as described above, creating at best an instantaneous burst of energy that deals damage and then dissipates.

In addition, because a vacuum does not conduct sound, any effect that must be heard is ineffective, such as a siren’s song or many bardic performances.

Speech cannot be heard in a vacuum, so language-dependent effects useless without an alternate means of communication, such as telepathy or magical or mechanical communications gear.

Warp Rust

Source Infinite Space: Hazards Stellar & Xenobiological, Copyright 2017, Louis Porter Jr. Design, Inc.

Starships traveling at high rates of speeds sometimes pass through clouds of xenobiological particles that adhere to the ship’s surface. Frequently known as warp rust, these particles feed on metallic substances and are capable of drifting silently through space – without nourishment, heat, or any external assistance – for thousands of years.

When warp rust detects the presence of a warm, metallic objects (such as a starship in flight) it releases built-up gaseous energy to propel itself into the path of the object.

Once attached to an object warp rust begins slowly eating at any metal surfaces, dealing 1d10 points of damage per minute.

Warp rust can only be destroyed through intense heat, such as laser blasts or the heat generated when entering a planet’s atmosphere. A typical patch of warp rust is one-quarter the size of a standard starship tactical space (the size of an ultralight ship) and has 20 hit points. Any laser attacks against a ship covered by warp rust deals as much damage to the ship as it does the hazard. If a character is attacked by warp rust the particles will feed on flesh – warp rust deals 2d6 points of damage to an unarmored character each round of contact. Decontamination systems will wash warp rust from an affected character.


Wormholes are random portals that transport vessels that travel through them to other parts of galaxies, or even to other galaxies altogether. There is no predicting where a wormhole will take you to except by exploring it, but there is some prediction as to where wormholes may occur.

Wormholes are unstable, and any vessel passing through it risks taking damage, or even the wormhole’s collapse. Any vessel passing through a wormhole takes 6d6 HP of damage. If the vessel’s pilot succeeds at a DC 25 Piloting check, the vessel only takes half damage. Should the pilot roll a natural 1, the wormhole collapses, inflicting 12d6 HP of damage to the vessel. Vessels destroyed in this matter are completely lost within the wormhole, as are their crews.

Once a wormhole collapses, it no longer exists.

Section 15: Copyright Notice

Starjammer – Starfinder Compatible Version © 2017 Open Gaming LLC; Authors: Peter K. Ullmann, Kirby Flake, John Starjammer – Starfinder Compatible Edition © 2017 d20pfsrd.com Publishing; Authors: Peter K. Ullmann, Kirby Flake, John Reyst, Troy Daniels, Michael McNeill, Manuel A. Oaxaca, Allen Snyder, Michael Ritter; Conversion to Starfinder by Tyler Beck, Kim Frandsen, Michael Ritter, Peter K. Ullmann.