Faster Than Light

Where We're Going, We Can't Use Eyes To See: Otherworlds And Faster Than Light Travel
The first thing one must understand other planes of the cosmos beyond the material is that they are dangerous.

This is pretty obvious on academic level, with thousands upon millions of records that bluntly state that the most one can hope for in FTL is only mildly creepy things happening. More than likely the warp drive messing with the fabric of the otherworld in question causes, at the very least, strange spatial anomalies where one can get an unpleasant (if harmless) look at one's own insides, or minor daimons (the Empire calls all entities that normally enter Twilight when in the mortal plane daimons) being swept up in the Serosa and wandering around the ship being creepy for the jump. The unlucky and unprepared often find that there can be worse things than Intruders in the planes. Some of the ships never make it back, and are encountered, devoid of all crew or populated by desperate mutant descendants of the original stranded crew, willing to do anything to see their ancestors' home (as a side note, so called "Voidborn" are a very marginalized minority, because nobody wants to confront the fact that they are unavoidable byproducts and victims of the expansion of Hireaconis).

The second, of course, is that if anyone wants to somehow get to other stars within the next thousand years, you need to go through them. Needless to say, FTL is not something done lightly. You want vacations, you go to sunny resorts in your own system (which, given how much of Empire power is centered in nobles-Awakened and not-usually means there's at least one resort planet per fully terraformed system for them to take sabbaticals in. One can usually tell how nice nobles are from how many of their house's common servants get to join them).

The exact mechanics of this depends on the warp drive-and thus, the otherworld it goes through-in question, but all depend on an Astrometric Serosa, a pocket of Rational Space (the term agreed upon for the reality of the mortal plane) that surrounds the ship and, to an unreliable extent, protects it form random dangers in the otherworld. Technically, the ship could enter many of them without said protection, and actually be safer in a couple cases-putting one world with different, ironclad physical laws into another world with usually flexible ones does not do wonders for dimensional stability. Ah, but there's the rub of it-that same chaotic "wake" is also a zone where normal physical laws simply do not exist, including the normal laws of relativity. No, it doesn't leave Paradoxes and Abyssal phenomenon in its trail; the very nature of the Serosa causes all the strange and exotic energies and particles to move with it and be reabsorbed into the fabric of the universe painlessly (unless that was the point; so-called "chaos drives" are the dynamos for the Scelesti to summon their legions of Gulmoth soldiers to wage their wars on existence). It does, however, rile even the most peaceful of daimons and generate otherwise impossible anomalies. Each set of anomalies is unique to every otherworld, but make no mistake-often, the first part of any journey is just preparing for the perils, let alone figuring out the path.

FTL Drives, and The Dangers They Invite
Stygian Skimmer: The most common warp drive, at least partially because the skies of the Underworld already have physical laws that allow for going faster than light. Not much faster, mind, but one can have a warp core failure mid-transit and still get out near a habitable system within the next decade or so. What's more, ghosts are naturally the most human and peaceable of daimons-hell, some of them even w'ere human at one point. The downside to this, of course, is that the only way to get out of the Dead Stars is a Stygian Gate, and while those aren't the least common thing in the world, they, like terrestrial cenotes, mostly formed naturally. As any idiot who has studied the natural world can guess, this often means they are frequently in the middle of nowhere, astronomy-wise. Thus, Skimmers are often packaged with another variety onboard anything other than the most civilian of civilian vessels, those meant for traveling between systems that are seats of the greater Imperial government (ie, those with actual Stygian Gates nearby for easy access). For the most part (ie, unless time or impatience is of the essence), all other ships travel to the nearest Stygian Gate to their actual destination, and complete the rest of the journey from there-the so-called "Station of Journey" strategy.

Dangers: Besides the fact that "least dangerous daimon" is a pretty low bar to clear, the Dead Dominions of the Kerberoi extend into space as well, and unlike the Autocthonous Depths/Lower Mysteries divide of the earthly Underworld, there is no clear delineation between neutral Void and Dominion Void. While the Skimmer's Serosa is confusing enough to the Kerberoi that they mostly ignore it, more than a few ghosts have been tasked with finding out what the mysterious disruptions in space and time are, and as soon as they sneak on board, many of them try to disable the drive within the bounds of their master's Dominion and strand the ship there, in the aegis of the Old Laws. While the commonly encountered Dominions have Old Laws that are well-known enough that most crews get out safely, there's always a few violations, at which point the alien guardian usually enslaves the living ship as a useful tool from the living world as part of the Enforcement. The tasks they assign to break free are often Herculean in scope as well, taking the crew (who are usually treated well enough to survive, however miserably) several generations to complete, if they are completed at all. By the time the ship finally limps back into Rational Space, the constant exposure over the years has usually mutated the descendants of the original crew into so-called Orphean Voidborn, strange mediums who seem simultaneously dead and alive...and have power over Twilight.

Primal Engine: The second most common form of FTL drive, and the one most frequently used apart from the standard Stygian. The Primal Engine is, as most Thrysus can guess, works by creating an artificial Verge and sending the ship through, often sending a few random spirits back across the Gauntlet in the process (this leads directly to one of the dangers of Shadow warp, but we're getting ahead of ourselves). About as fast as assisted (ie, with Skimmer engaged) Underworld travel, a Primal Engine is also infinitely more flexible-anywhere can play host to a temporary break in the Gauntlet, therefore anywhere can be a destination. What's more, the Engine's running is also rather...pleasing, shall we say. As is implied by the name, its actual mechanics involve summoning a small bit of the Primal Wild inside of it, and exposure to the purest form of all nature excites the lizard brain. While no intelligence is actually lost, the crew of a Shadow-traveling ship has simpler, less complex emotions than normal for sapients, and while wild animals can and are disturbed by being stuck on a cramped starship, the sapient instinct is more like a domestic beast; it relaxes so long it has something to do. Thus, Shadow travel is often less traumatic then other varieties can be.

Dangers: Domestic animals can also be mean little buggers if upset, and the affected crew, besides quite possibly becoming addicted to the experience (never fun), can and will act on their most pressing repressed impulses. Besides quite possibly resulting in a bouncing bindle of irritation if there is a large amount unresolved sexual tension, this also means that an unhappy crew going in can turn riotous, and while thankfully the instinct towards altruism and selflessness is basic part of social animals (which is why there aren't more murders), more than one captain has found they should have screened for sociopaths beforehand. This isn't even getting into the fact that the Primal Wild does not enjoy being contained; the ship needs to constantly be scoured for warp creeper, a grey-colored semi-sentient vine that is attracted to the Serosa and quietly invades the ship, hoping to sneak into the warp drive and bloom. As one might imagine, the pollen of warp creeper is perfectly suited for knocking it offline, leaving the ship at the mercy of the Shadow...assuming the spirits who usually wind up on board somewhere along the way decide that the Essence generated by a stranded ship would be perfect for them. And not just conceptuals of emotions like panic or loneliness-a stranded ship tend to get stuck in a Place-That-Isn't consisting of the former Astrometric Serosa, which quickly matures into its own habitable pocket dimension filled with strange and exotic forms of life-a boon for the crew trying to survive, but an even greater boon for the spirit courts in general wanting to eat something other than void Essence in space.

This leads to the second danger, the fact that artificial Verges tend to eject spirits into Rational Space. While most immediately go back in the second or so before the Verge closes, the simple fact of the matter is that if there is something in the mortal world, there's a spirit somewhere who wants to go across the Gauntlet to get it. While this isn't necessarily a concern for departing vessels (unless the captain isn't a fan of people with knives possibly waiting for him if he comes back), a returning ship must always keep this in mind, especially if they're going to a place with known Wounds. Thus, most inhabited worlds establish a "safe zone" which Shadow warp cannot be ended in; a precaution to remain as uninteresting to spirits as possible via forcing them to weigh the risk of starvation vs actually reaching the Essence. This has had mixed results, but it's something.

The good news is that a vessel stuck in the Shadow can still get home on its own initiative, though it requires a lot of negotiation with spirits who understand perfectly that their little dimensional garden will dissolve after the ship is out; more than one large-scale spiritual incursion was as part of a payment for passage home. The better news is that a Serosa turned Place-That-Isn't has a very distinctive dimensional signal that rescue crews are specifically trained to look for. The bad news is that the Shadow, as a fundamentally living world, is even more mutative than most Otherworlds-even a month causes subtle but far-reaching changes to the genetic code of the stranded, and while they don't normally transform into Voidborn themselves (they usually escape or die before they hit the one-decade point), any children they have has a vastly-increased chance of being Voidborn.

Primal Voidborn are worth a a paragraph on their own; they vary wildly, including, but not limited to, a subspecies of mutant that is permanently Spirit-Claimed (any attempt to expel the spirit results in another taking over the Claim), Pseudo-werewolves (always a non-wolf animal, and not really as stable, nor as powerful as the real thing), the Verdant (who can make anything grow), the Adaptable (who can quickly adapt to any enviroment, and who are kept away from FTL environments for subtly obvious reasons), and many others. The most common and dangerous Primal Voidborn are the Ractain, who are born without a nose and with a tendency to become Patient Zero of an Abyssal plague and/or Awaken as a Mage. The silver lining is that this is well-known problem, and there exist genetic therapies to correct the Shadow-influenced DNA, though actual Ractain are stuck as mutants. The worse news is that many spirits are perfectly aware that the end stage of the disease is becoming the foundation of new loci, and while the Abyss inspires an instinctive revulsion in uncorrupted spirits, a few particularly greedy ones (and more likely, amoral shamans) are known to sabatoge the process, and with it create new hosts for the Shadow Plague.

Pandemonium Nexus: The last of the common drives-which is to say, those who use it on a semi-regular basis can still have some claim to sanity. Contrary to the hellish implications of its name, the Nexus does not use the Lower Depths as its Otherworld, but rather Astral Space, using the conceptual nature of the thought-realm to travel exponentially faster than its more commonly used cousins. This is due to two things-one, sapients only have an academic understanding of what "the speed of light" entails, something the Nexus abuses to great effect, the second being that it is still a device of Pandemonium, and thus quite capable of warping the fabric of space itself; it's own selfsame wormhole. Navigation with such a device is also surprisingly simple-just punch in the coordinates and the Nexus is quite capable of figuring out much of the needed equations to warp to the intended destination on its own. It's the actual jaunt that's the difficult bit, and that's more due to the weird Serosa effect rather than any trouble with actually arriving at Point B.

Dangers: There's a reason it's not used more often-a relatively benign side of Pandemonium is still Pandemonium, and thus, the Nexus seems to deliberately select for the more hellish (pardon the pun) environments of Astral Space. Also, notice the term "Astral Space", not "the Temenos" or "the Anima Mundi"-it criss-crosses through all of them at different points, and not necessarily those of the same race as the crew. As one might imagine, it's experiences with the Nexus that inspires all the horror fiction about things one finds in warp-there is literally no limit to the sapient imagination in its ability to horrify and torture itself, and in Astral Space, the delineation between "nightmare" and "reality" is extremely flexible.

And that's just the dangers of the Otherworld itself! To put it simply, the kind of spatial warping the Nexus' Astrometric Serosa creates is what one would normally list under "open portal straight to Abyss, do not pass Go, do not collect 200 tass". Since the effects do not actually draw power from the Supernal, simply emulate it, the Nexus does not normally summon Intruders (unless it has been modified into a chaos drive), but one of the things young Mastigos quickly learn is that their magic is scary on a primal level; it is not uncommon for ship components to temporarily warp into mazelike tesseracts for a few hours or more, or for crew to suddenly find they are looking in different directions then they are facing. If the warp goes somewhat well, these spatial anomalies are rarely harmful, though enough are that a medical bay with specially trained doctors is recommended on every vessel with a Nexus.

If all does not go well, however, the crew of a Nexus ship can take hope that at least they are usually destroyed outright or dumped in a remote gravity well (never in the event horizon of a black hole, however-even catastrophic collapsing of a spatial anomaly has limits) rather than trapped in the Astral-thought does not have an easy time containing the physical. To actually get stuck in Astral Space requires that the Nexus gives out/is sabotaged by hostile daimon or insane crewmate (this includes spies, as no one with a lick of sense thinks it is a good idea to sabotage a Nexus in transit) during a particular, uncommon spatial anomaly in the Serosa called a "Weir Pattern", a state in which the ship exist in the Dreamtime and Temenos simultaneously. If the ship is brought down during a Weir Patten, the Serosa enters a strange sort of meta-stability in which it simultaneously grows more chaotic and yet more resilient-a pocket universe made of psychic energy. Within the so-called Wraith Realm, reality goes out to lunch, as time, space, and thought lose distinction, intermingling and separating at their leisure. A crew that does not go insane in short order quickly drops any pretense of normal organic existence, learning how to accept thing as both illusion and reality, both dream and waking. It isn't a pleasant existence, and even the long-removed descendants of a crew are confronted with the idea that they are not "home"-a Wraith Realm is still part of the Astral, after all, and regularly intercepts thoughts from Rational Space. If it is any comfort, the dreams can be sent back, and indeed, there's a thriving-if niche-industry in finding Wraith Realms and bringing the stranded back, both for the ship's cargo (it would be stupid to send such a fast yet dangerous ship drive out without it containing something of incredible value), whatever weird and interesting chimeric items were picked up in the pocket between Temenos and Dreamtime...and the Compatior Voidborn.

Despite the apparent chaos of a Wraith Realm, the Voidborn who arise from there are singular in their distinctiveness-namely, a "third eye", a node on their forehead that, if examined in Mage Sight or by scrutinizing their auras, resembles a field of falling stars. This is a direct link to Astral Space and the bizarre relationship it has to Rational Space. There are usually other mutations that mark them as distinctly other, but the third eye is most obvious. Besides being an interesting topic at parties, the third eye is also a sort of "backup brain" that contains a unique neural network exclusively used for psionics, sensory processing...and most importantly, a special sense for the very fabric of space-time, making the Compatiori peerless navigators, if more than a bit frightening. This, combined with their high rate of true Awakening-even compared to other Voidborn-makes them a sort of aristocracy of the mutants; not trusted, not accepted, but certainly tolerated and, in certain cases, celebrated for existing. It is, perhaps, the universe's apology for the hell of the Wraith Realm.

Rumors of corrupt nobles and Left-Handed Mages deliberately rigging a Nexus to turn itself off when a Weir Pattern occurs, then organizing missions a couple months later to reap the matured Compatiori are, of course, unsubstantiated.