Tuesday 17 August 2021

Mothership: Further Thoughts

In my previous post I gave a few thoughts on a rough Mothership setting. Have some more. Note: I am not a physicist so the below is probably very wrong. As I have now disclaimed this fact you can't be mad at me.


Marnix Rekkers

I previously mentioned that:

Starships are many and varied. They share this in common: Newton's laws are supreme, artificial gravity is provided by acceleration G- or centrifugal force, and waste heat is a constant enemy. Expect rotating crew quarters, G-force couches, heatsinks and radiators, and barebones design. Very few spacecraft are able to touch down on anything near Earth-gravity planets due to their non-aerodynamic design and the fact that many use fusion torches for void propulsion which would eject a nasty amount of fallout into a planetary biosphere - most have a spaceplane and/or rely on some form of orbital infrastructure to reach ground level and return to orbit...
As I'm aiming for a reasonably hard sci-fi approach (magic FTL notwithstanding) this presents a couple of circles to be squared in the Mothership Player's Survival Guide, in no particular order:

  1. Fighter-class ships
  2. Thruster speed, fuel use, and alternative propulsion
  3. Jump drives
  4. Stealth, G-forces, weapons, and heat
  5. General ship design points

Fighter-class ships

Do not exist. Allow me to explain. Warplanes fulfil a niche in terrestrial warfare because they're fast and mobile, can attack targets beyond the horizon out of sight of your big slow vehicles and ships, and they can move through the atmosphere reasonably efficiently. In void warfare there is no horizon preventing your big guns from targeting the enemy directly and there is no atmosphere whose constraints you must consider while moving - there is no reason to close to knife-fighting range.

Furthermore, an atmospheric fighter has the advantage of not requiring life support (beyond compressed air and heating for high-altitude flight) and being able to rely on atmospheric drag and planetary gravity to aid in braking. Void craft do not have this luxury - organic crew require life support, increasing the mass of the craft, and rather than braking via drag a spacecraft must apply thrust in a different direction to slow down/change vector which requires fuel and applies (potentially fatal) G-forces to the organic pilot depending on the acceleration/deceleration. Factor in the additional mass/energy requirements for ammunition or other weapons and you add a greater need for fuel as more mass = more energy to move said mass.

The final knife in the coffin, so to speak, is survivability. Void warfare stands to be a slugfest - there's no 'cover' in space short of hiding behind a planet so once a fight starts you're almost guaranteed to be hit by something as CIWS and EM countermeasures will never be 100% successful. Surprise, physics rears its head again here - a critical factor to consider in a void battle is the amount of surface area your ship has vulnerable to attack as this presents greater opportunities for your enemy to penetrate your hull and smash up vital systems. More surface area will require more armour to protect, which means more mass, more fuel etc. etc. etc.. It may seem like a small fighter would make sense then, as it's smaller and has less surface area. However the laws of physics dictate that the more massive an object is, the lower its surface area proportional to a less massive object. This has huge ramifications for void warfare - a larger ship is inherently more massive with the difficulties that entails but you enter a sort of economy of scale beyond a certain point. You can have a large vessel with high mass but if you arrange it in a compact shape you can concentrate said mass into a low-surface area, pile your crew and vital components in the middle surrounded with armour and end up with an order of magnitude more survivability than a fighter-size vessel. Add the fact that a larger vessel means a bigger reactor and storage room = more missiles, railgun rounds, bigger, better lasers, more fuel (and thus greater delta-v capacity) and bigger engine (meaning better acceleration) and it's a no-brainer. Space fighters are vulnerable, weak and limited in range and scope.

A far better solution would be to strip out the life support, up the armour, reactor and weapons and install an expert system with a control link back to a command ship - essentially turn it into a drone. Or use more missiles. Either way you avoid sending fleshy pilots to almost certain doom.

Ben Nicholas

Thruster speed, fuel use, and alternative propulsion

Speed is a bit of a red herring in space as everything moves super fast - being in an orbit is essentially moving laterally quick enough to miss the ground as gravity pulls you down. As such, any spacecraft is capable of picking up fantastic amounts of speed but what really matters is the ability to change speed and direction and the acceleration/deceleration forces one can bring to bear - delta-v is king. The Mothership core rules use Speed as a catch-all movement stat for starships - it's used for determining the success of complex piloting manoeuvres and as a measure of speed relative to other ships. More ship Thrusters = higher speed in the rules as written. There is also the concept of Fuel, which is used to activate the Jump drive (requiring double the Jump rating in fuel) and using thrusters burns 1 unit of fuel/day. Each engine unit also requires 3 fuel, plus additional fuel as required*. All perfectly serviceable, but not hard sci-fi enough for what we're aiming for:

  • Starships do not need to fire their thrusters to maintain a continual speed, only to accelerate/decelerate or change direction, thus there is no flat usage of fuel per day when travelling in space.
  • I think an 'Engine' probably refers to a reactor of some kind as it references powering the whole ship. I will treat it as such. In a fusion drive (assuming direct thrust) the thrusters function independently of a ship's reactor, fusing He3 and directing the exhaust out the back of the ship, which breaks the required link between Engines and Thrusters in the ship design rules. I like the idea of a ship's reactor powering the Jump drive.
  • A larger drive (in this case higher thruster level) does allow for greater speed/acceleration (specifically a bigger rocket can produce more thrust) but each manoeuvre undertaken by a starship requires fuel to change speed and direction.

*Note: I don't quite get this bit as fuel adds to the total hull requirement but can be stored in cargo space - maybe they mean dedicated fuel storage? - also the engine units can apparently burn fuel at a rate of 1/day under thruster power but require a minimum of 3 fuel each when building the ship?).

With the above in mind, I'd propose the following reforms:

Interplanetary Travel - Thrusters & Fuel

In a ship equipped with a fusion drive burning He3 Speed represents the maximum acceleration possible by a ship. Keep the current thruster > speed relationship as written - a larger thruster means higher acceleration can be reached.

Instead of burning 1 fuel/day of travel instead divide a system into zones of interest - a 'zone' is a planet (and its moons), star, deep space observatory etc.. Basically anything interesting in a system and its surrounds is a 'zone' and travelling between these locations takes at minimum 1 unit of fuel to get up to speed and decelerate when approaching the destination. Zones are stacked from the inner system to the outer edge so to travel from an inner system zone to an outer system zone you'd need to account for travelling through the intervening zones. As larger thrusters mean more fuel can be used they can achieve higher acceleration - a ship with a speed of 10 can only burn 1 fuel, but a ship with 20 can burn 2, a ship with 30 can burn 3, and so on.

A ship burning a speed 10 fusion torch can travel from one zone to another in 4 weeks (based on Project Rho's low-end torchship calculations). Burning additional fuel in a higher-rated thruster reduces this travel time exponentially:

  • A speed 20+ ship burning 2 fuel will make it in 2 weeks.
  • A speed 30+ ship burning 3 fuel in 1 week.
  • A speed 40+ ship burning 4 fuel will make it in 4.5 days.
  • A speed 50+ ship burning 5 fuel will make it in 2.25 days.
  • A speed 60+ ship burning 6 fuel will make it in just over a day.
  • A speed 70+ ship burning 7 fuel will make it about half a day.
  • A speed 80 ship burning 8 fuel will make it in ~6 hours.

The latter stages begin to get into the region of relativity but the distances travelled are generally so short (astronomically) that this won't have much of an effect. Established planetary governments do, however, tend to take issue with objects approaching c near them and so generally enforce a sort of stellar speed limit (the penalty for speeding is nuclear annihilation and/or parking something in your path before you can turn). A major issue with travelling at the higher tiers is the sheer amount of fuel needed to do so - unless you're in a real hurry and/or have very deep pockets it's usually easier to sit in the slow lane and enjoy the downtime - and the G-forces involved on the crew in such a rapid acceleration over a relatively short patch of spacetime (speed 80 = ~10g for several hours).

This is of course an abstraction - a speed 10 ship could in theory perform subsequent or continual burns to speed up but my reasoning is that zone-to-zone travel on the scale of fractions of AUs means that by the time a smaller thruster has completed its initial burn (larger thruster = more propellant can be fired at once) and accelerated they're either at or approaching the point where they need to perform a retrograde burn to begin decelerating on approach to their destination. This also ignores the movement of planetary orbits, I've tried to take an 'average' value rather than spending time calculating the 'season' people are travelling in.

What can I say? I'm not actually a rocket scientist.

Interstellar Travel - Thrusters & Fuel

If you're not using a Jump drive then the Warden can rule this as they see fit. Using the above example a speed 80 ship (assuming zone-to-zone travel on the scale of 6 hours/AU (150 million kilometres)) accelerating at 10g could cross the distance between Earth and Centauri (~4.25ly) in about 9 months with a time debt of ~4.5 years. However, this would take absolutely astronomical (heh) amounts of fuel - assuming a dry weight of 500 tons would mean over 1 million tons of fuel required to maintain constant acceleration. The ship would almost certainly have to coast for the majority of the journey, which would massively increase the time taken - potentially up to centuries.

Intergalactic Travel - Thrusters & Fuel

No chance.

Alternative propulsion and planetary landings

The above assumes the widespread use of relatively efficient fusion drives throughout human space, but there are other options available as well for systems with well-developed stellar infrastructure.

Solar sails are a viable and cheap option for intra-system travel - bind aluminium to a tough but flexible polymer sheet, make the sheet a sufficient size (kilometres across - an 800m square sail catches ~5 newtons of force at the Earth's distance from Sol, which drops as you get further out) to pull the payload at a suitable speed and let the sun's radiation do the work. Using gravity assists and solar wind alone means for a relatively slow journey, but with sufficiently advanced space infrastructure it would be quite trivial to set up a laser network capable of accelerating/decelerating solar sail craft. As a general rule assume a solar-propelled craft can travel zone-to-zone in about 6 months when receiving a gravity assist from a star (based off the predicted travel times for our solar system). If laser-boosted, however, use the travel times per fusion craft with speed scaling according to the system's development. A system with a laser propulsion network may well require craft approaching void habitats or inhabited planets to deploy a sail and use specific 'space lanes' rather than letting lit fusion torches near habitable worlds - anything capable of applying the energy required for such high acceleration essentially has a huge weapon attached to its rear end.

Ion thrusters have the advantage of being very efficient and can reach high speeds given enough acceleration time but are unfortunately not very powerful. They're useful for deep-space probes that will be travelling for decades and centuries, satellites/stations readjusting orbits but generally lack utility on spacecraft.

In general assume that starships are designed for use in space only and cannot land on planets with an atmosphere and/or anything higher than lunar gravity (0.166g). As I mentioned previously, most will have a dedicated aerodynamic spaceplane either independently capable of single-stage-to-orbit flight (using new types of rocket fuel, dual scramjet/rocket designs, nuclear lightbulbs, or another solution) or relying on assisted launches from launch loop(s), orbital infrastructure like an orbital ring, and/or space elevator(s) (which would remove the need for a separate orbital vehicle entirely). A developed planet with similar gravity to Earth would be able to provide the former but a less developed frontier world may rely on skyhooks or old fashioned chemical rocket launches. The lower the gravity of a given planet, the easier achieving orbit is - low gravity environments can easily achieve orbital trajectories via mass driver, for instance, whereas Earth-gravity planets would need to supplement such a solution with additional thrust from rockets or ground-based lasers.

space gooose

Jump drives

In the Player's Survival Guide actual Jump distances and procedures are left up to the Warden but are stated to be subject to irregular effects of relativity. My adaptation for this is as follows:

Jump rating is the number of parsecs that can be crossed per week (as perceived by the crew) in hyperspace. Jumps always take 1 week from the crew's perspective. Entering hyperspace requires a starship to be at the edge of a system's gravity well in order to create a stable hyperspace bridge - the Jump drive works by searching for a suitable 'mass shadow' and plotting a hyperspace course towards it. The ship can exit from hyperspace once they reach the limits of the target system. Attempting to Jump while within a system is virtually guaranteed to end catastrophically. The real time spent in hyperspace can vary, but on a well-executed Jump on a reliably-plotted route crew time and observer time will generally match, and any route with a known timelag can be accounted for.

Hyperspace is, by its very nature, alien, corrosive, and counter-intuitive to human minds and the very properties that allows starships to bypass relativity when travelling through hyperspace also lead to hyperspace routes shifting and changing over time. Most spacers liken hyperspace to an ocean with tides and currents - by mapping and plotting reliable routes travel disruption can be minimised, and most port authorities demand that berthing ships share anonymised hyperspace route data as a condition of receiving services. This data is then used to update the minute shifts in hyperspace conditions for the given route and is transmitted out to other ships for navigation purposes. Jumping into a less travelled route could mean that hyperspace conditions are wildly different to what the data indicates - most of the time this will mean a greater outmatch between observer and crew time but sudden and violent shifts (so-called 'hyperspace storms') can lead to ships arriving months or years late, at wildly different destinations, or even suffering damage and destruction at the hands of surging metadimensional currents. Bear in mind that this data sharing relies on receiving regular traffic - a backwater system may not be able to provide up-to-date course bearings if you're the only out-of-system ship they've seen recently.


Jump procedure

A ship's computer is able to plot and execute a Jump based on the most recent astrogation data available - it will tell you the status of the route:

  • Uncharted/untravelled for >1 year - timelag effects unknown, high likelihood of danger to ship and crew.
  • Untravelled for 6-12 months - likely timelag ≥1 Standard year.
  • Untravelled for 2-6 months - likely timelag of 1d6 Standard months.
  • Untravelled for up to 1 month - likely timelag of 1d4 Standard weeks.
  • Travelled within last 2 weeks - time asynchronicity within acceptable parameters.

It will also mention any known hyperspace conditions, like known danger zones or patches that slow or speed travel for whatever reason. I've not done a list for these as I figured that the above would be sufficient and additional features can be made up on the fly as appropriate.

If attempting to plot a Jump while in combat or undertaking some other stressful task an Intellect/Astrogation or Hyperspace check may be called for - the Warden can determine any deleterious effects caused by a failure. Radiator panels and other external instruments are normally retracted if possible to keep them well within the realspace bubble.

All organic crew must enter cryosleep for the duration of the journey and androids a hibernation state. The effects of hyperspace on the human psyche are well-documented - human minds gradually deteriorate if left awake while undergoing a Jump. Chillingly, a similar effect is seen in active persona cores leading to an intense study on the effects of hyperspace on conscious minds and lending credence to the idea of strong AI personhood - weak AI software appears to suffer no ill effects. Any characters awake in hyperspace must make daily Sanity saves.



Stealth, G-forces, weapons, and heat

There is no stealth in space, with some caveats. I mentioned previously that fighter aircraft make sense on Earth due to the existence of the horizon - the higher up you are the further away the horizon is and thus the further you can see. Space has no horizon - everything not blocked by a stellar object can be seen, the only limiting factor is the amount of time it takes for light/radiation from the object to hit your sensors. And there will be emissions from your ship. Space is big and dark, which sounds like it would be a great place for hiding but all it does is make the big plume of heat emanating from your drive extra-visible to your opponents' sensor suites - while humans are lazy and prone to error, a shipboard electronic warfare suite will be able to home in on a fusion drive signature on the other side of the system in seconds.

So, what if you don't light off your drive and rely on gravitational slingshots to send you on your way? Unfortunately, every action taken on a vessel creates waste heat (thermodynamics is a bitch). Space, being a vaccum, makes it impossible to conduct this heat away as one would in an atmosphere. As such a spacefaring vessel is equipped with extendable radiator panels that emit this waste heat as infrared radiation - the moment a starship begins dumping heat it might as well light off its drive, though this can be mitigated by radiating away from the target's sensors. So what if you do this, running your ship in minimal power mode with internal heatsinks absorbing as much waste heat as possible and radiating the rest away from obeservers? Unfortunately your ship will still be emitting detectable IR radiation, even if coated with a 99.99% non-reflective substance. There's also the problem that you'd need to keep some reactor functionality going to keep basic functions running which will have its own hotspot signature - if a space telescope can detect the Voyager probe 18.5 billion kilometers away radiating the approximate energy of a fridge lightbulb then advanced starship sensors can spot you, though they'd probably need to be actively searching for you. You could try beaming the waste heat away via laser, but due to the laws of thermodynamics this would take additional energy to do thus increasing the waste heat total and be less efficient, to boot. It's also easily spotted by an observer using a network of sensors rather than their own ship. Also, to refer back to the point of burning and then coasting, if anyone detects your initial burn and trajectory they'll be able to predict where you're going and your ETA with a high degree of accuracy.

What about decoys? They're really, really hard to get right. Anyone with half-decent sensors will be able to read your drive signature and acceleration, thus being able to approximate your ship's mass. If you send off a bunch of decoys you'd need to make them with almost identical drive signatures and masses otherwise it would be obvious, essentially you'd need to recreate your ship. Note that this is only relevant to a stealth situation - in active combat decoy signatures can be a vital part of ECM and make or break a ship's survival.

Active and passive sensors do need to be accounted for. Active sensors use LIDAR or some other electromagnetic detection suite to actively 'ping' a target and read a reflection of the sensor's signature. Passive sensors instead simply observe and take in data from the environment without actively broadcasting a signal. Running active sensors allows for quicker and more efficient target identification as you're able to actively seek out and get a response from an otherwise inert target, but it has its downsides. Using active sensors is akin to flicking a torch on at night - it improves your vision but everything in the dark knows exactly where you are. Passive sensors are less precise, but also don't reveal where your ship is.

Stealth, for the most part, is best done by hiding in plain sight - disguise your vessel as a shipping freighter, engineer a distraction to draw attention away, and as a last resort by shielding yourself behind interstellar objects. In game terms starship stealth can be dealt with as an opposed Intellect check (Astrogation or Vehicle Specialisation (Starship) possibly applying bonuses), with the following applying:

  • If running cold and from a hidden starting burn (Warden rolls a d100 setting the chance of being spotted as they deem reasonable, i.e. hidden asteroid base or gas giant outer atmosphere is plausible; undocking from a major spaceport is not - it's rare that anywhere is completely unobserved) then the party in stealth rolls with advantage.
  • If the searching party is using active sensors they roll with advantage.
  • A ship undergoing a burn, dumping heat (unless doing so in the opposite direction to the target), or running active sensors is not capable of stealth - its presence is obvious to any observer.


G-forces are a perennial foe of spacers. While a fusion torch can produce fantastic amounts of acceleration, old Isaac Newton takes his due in the form of Newton's Third Law - every force is matched by an equal and opposite opposing force. This g-force can wreak havoc on crew and ship alike - a hasty manoeuvre at high acceleration can leave a crew member as nothing more than a smear on a bulkhead. At the same time g-forces created during normal acceleration and deceleration are either not enough to fully recreate Earth gravity aboard a starship or much too high, requiring rotating crew quarters to provide centrifugal force to simulate 1g effects (we're not in the realm of constant 1g acceleration yet) and crash couches to support the passengers during a high-g burn. As such much of a space voyage is spent in zero-g when outside of the rotating quarters. Tracking g-force will only really come into effect during combat manoeuvres.

When making a combat manoeuvre (i.e. taking evasive action against torpedoes) the captain must choose what speed the manoeuvre will be made at:

  • At speed 10-30 all passengers must make a Body save or suffer 1d10 damage and gain 1 Stress.
  • At speed 31-50 all passengers must make a Body save or suffer 2d10 damage and gain 1 Stress.
  • At speed 51-80 all passengers must make a Body save or suffer 3d10 damage and gain 1 Stress.

Similarly all passengers must either be in crysosleep or a crash couch whenever the ship undergoes a burn or be subject to the above - save against Speed instead of Body as you struggle to find a brace position against the sudden acceleration rather than straining against the g-force.

The starship weapons in the Player's Survival Guide are great, but need a bit of reworking. Our ships will be engaging at hundreds of thousands kilometres with near perfect visibility, as such the existing ship weapons are as follows:

  • Laser Cutter - designed to fire at relatively low power (it's cheaper for mining rigs). Useful as a last ditch weapon but no match for an armoured starship - targets roll Armour with advantage. Conversely a dedicated laser turret is far too powerful to reliably ablate and process asteroid resources, reducing the rock to slag.
  • Autocannon - unfortunately not really viable on the scale of starship combat. Useful as a drone mounted weapon in conventional combat where it does D% damage.
  • Railgun - now we're talking. Even though the distances in starship combat are massive, being able to accelerate a stream of kinetic kill slugs at massive speeds into the predicted path of your enemy has its perks. Leave as-is but need to factor in heat use (not as much as a laser, but still decent).
  • Mounted Machine Gun Turrets - use as-is, useful for mounting on spaceplanes and atmospheric craft.
  • Torpedoes - the real stuff. Nuclear-tipped or not, a projectile that can adapt to your opponent's position, home in on their active sensor signatures and overwhelm their point defence all while not burdening you with increased waste heat is a valuable tool.
  • Rigging Gun - useful on tugboats but useless in a fight. Utilises a magnetic grapple.

I would also add the following:

  • Laser Cannon - essentially replaces the autocannon, trading kinetic slugs for pulses of high frequency lasers. Doesn't use ammo but produces prodigious amounts of waste heat despite advances in laser efficiency - that's the price for being able to target an enemy at the speed of light.
  • Combat Drone - a small decoy/weapons carrier capable of interfering with enemy sensors and weapons via ECM or occluding agents or deploying torpedoes/kinetic kill vehicles. Usually programmed with combat parameters before launch and updated via tightbeam (at least until EM interference gets too bad) - usually released in a swarm to overwhelm enemy point-defence.
  • Close-In-Weapons-System - small laser point defence grids designed to defend against incoming torpedo fire and general debris. The lasers usually can't destroy the missiles outright but even a small jolt can ablate enough material to interfere with speed, vector, guidance and payload delivery, thus enhancing your survivability.
  • ECM Pods - specialised electronic warfare suites that interfere with target acquisition and communication in the electromagnetic spectrum.

As most of these weapons will rely on the ship's reactor for power I'm going to add an Engine requirement for the majority of them to ensure they can be run adequately. Then there's the thermal waste generated to consider...


Heat is the other perennial enemy in space. Everything, from firing weapons, scanning the dark reaches, to simply keeping the air and water flowing, incurs a waste heat debt which can't simply be conducted into the vacuum of space. Luckily starships have extendable radiator panels that can radiate this heat away as infrared radiation. Most starships will keep these extended and radiating in order to keep their heat debt to a minimum - thus marking them out clearly to sensors against the cold background of space. Ships committing to high-g manoeuvres will often retract them to keep structural strain to a minimum and all ships in or anticipating combat will retract these vulnerable lifelines of their ship to protect them from weapons fire. Internal heatsinks provide precious additional time to keep radiators retracted in a battle but eventually even these will give out. Thus fighting represents a constant ante between ships attempting to damage each other while maintaining their own waste heat within reasonable limits.

In game terms each vessel has a heat tolerance representing their ability to endure waste heat before it needs to be dumped. This is determined by the overall hull size of the ship (I can't figure out a way to take surface area into account without going into a minutiae-fest so the more hull points you have the more heat you can diffuse throughout your ship because you have more internal heatsinks, or something). Each 10 points of hull gives 1 heat capacity. Actions in combat like firing (most weapons), performing a burn, or powering up the Jump drive incur a heat cost - once the heat tolerance theshold has been reach the radiator panels must be extended to dump heat or on the next turn the ship suffers a Critical Hit caused by overheating subsystems and all crew members must make a Body save or suffer 1d10 thermal damage.

If a ship has its radiators extended and suffers a hit roll a d10 - on a 1-5 in addition to dealing hull damage subtract the same amount from the target's heat tolerance.

I'll be doing a wider section on starships in a later post with some more fleshed out rules for space travel and combat.



General ship design points

A few final points to consider:

  • Even though fusion torches allow for Brachistochronic trajectories between orbital bodies rather than relying on Hohmann transfers, mass is still an important consideration. Ships will be built as spartan and barebones as possible to save on fuel. This won't have a mechanical element (I'm not masochistic enough to try and puzzle out a relationship between hull and fuel) but is more of a descriptive one - think exposed bulkheads, plain decoration and minimal personal effects.
  • Most crews will spend the majority of their time in zero-g outside of rotating quarters. Corridors and walls will generally be rounded with padding (to prevent too much damage when losing control in zero-g or, more likely, being suddenly subject to a different g-force during an unexpected burn) and grab loops regularly spaced to anchor and propel oneself while weightless.
  • Fancy tech with bells and whistle is great but when you're travelling through a medium of certain death in a sealed metal can you want reliability above all - manual backups and workarounds, robust computerisation, the works. This is so I can have Alien-style retrofuture style tech justified in-game.
  • Ship combat is deadly - expect even unarmed ships to possess some degree of armour. As a corollary to this many battles will end with one side surrendering when their radiators have been slagged and they need to shut down their reactor to prevent themselves from roasting alive.
  • In terms of ship structure you'll see a difference between explicitly military ships and not - combat vessels will want to concentrate their mass as much as possible in order to armour up their vital components, civilian ones probably don't mind spreading out in a length as it's cheaper - but most spacecraft will be built upon similar lines: thrusters, power plant and fuel towards the back, cargo space in the midsection and crew-critical areas at the other end. Alternatively, ships could use a more spherical shape with the reactor and drives extending from the rear. There's a plethora of plausible designs. You'd probably see a lot more standardisation in the Core, with different designs becoming more common the further towards the Beyond you get.

Wednesday 11 August 2021

Mothership: Thoughts

This post is brought to you by Dan, RimWorld and NewSovietWave.

I started writing a post last year that I never ended up publishing which was intended to be a review of sort for Mothership, from Tuesday Knight Games. My review is as follows:

Mothership is pretty great.

Normal service will now resume.


Glenn Clovis

I ran a small adventure for some friends of mine using the core rules in the Mothership Player's Survival Guide not long after picking it up. It was fairly simple - the PCs were passengers on a ship who awoke from cryosleep to find the vessel stranded in a system's Oort cloud with the laws of physics behaving weirdly, the crew having gradually been driven insane and consumed by an energy-vampire entity that lived in interstellar space mostly interacting with dark matter. They loved it, and most of them even survived! Since then I've been thinking about it on-and-off and have a few ideas about a general setting.

The below is mostly predicated on the existence of non-relativistic Faster-Than-Light and the theory of the mind as essentially non-computable. I've got a few ideas for a subsequent post where FTL travel incurs serious time-debt and Dan has some excellent stuff on digital posthumanity (it's great, go read his blog).


Some time in the mid-late 22nd century. The exact date doesn't matter a whole bunch for a few reasons:

  • Mothership is a pretty lethal system and having a vague idea of time works easier for me to drop a new party into rather than strictly defined chronology.
  • FTL travel, while not strictly relativistic, has its vagaries with regards to the passage of time for both travellers and observers.
  • FTL communication isn't possible - information travels at the speed of the fastest ship - leading to a large information timelag the further across space one travels.

Time is still generally tracked on a 24 hour day ((Earth) Standard Day) and 365 day year ((Earth) Standard Year) largely out of inertia, but decimal time is also popular on starships. Extrasolar residents will usually keep a parallel Local time system.


Human space is laid out in three rough concentric spheres centred around the Sol system, comprising a diameter of ~300 parsecs (Rigel here we come!):

The Core sphere

The space occupied by the initial extrasolar colonisation efforts and, thus, the oldest and most developed worlds. Travel time between these systems is reasonably quick and the relative speed of information and travel results in the Core largely existing under the iron fist of UN Intersolar Authority (UNISA) with centralised government (read: corporate) structures, component standardisation and elements of cosmopolitanism. Also the region of space that bore the brunt of the PERIMETER Crisis - the Sol system is still cut off from hyperspace. You can get from one side of the Core to the other in about 3 months in a Jump 4 ship.


The Outer sphere

The space colonised by the second wave of Terran efforts. The UNISA still holds authority here though their structure is necessarily decentralised given the less well-established hyperspace routes and distance from their Core strongholds. As such nominally independent 'sovereign system' polities have emerged - this process has accelerated in the wake of the PERIMETER Crisis as requisitions and taxes have been levied by colonial authorities to assist in Core reconstruction efforts, sparking brushfire wars and insurgencies. Travelling from the edge of the Core to the boundary of the Outer sphere takes about 6 months at Jump 4.


The Rim 

The far frontier holding the furthest documented human colonies in the Milky Way. Hyperspace travel is still risky and unpredictable here and the authority of the UNISAis virtually unrecognised and grows weaker every day. Cult leaders, political dissidents, corporate prospectors and more congregate at the fringes of human space and society. To travel from the edge of the Outer sphere to the loose boundary of the Rim takes around 9 months at Jump 4.


The Beyond 

Non-colonised (officially) space past the boundary of the Rim.


Most of us could be transported into this setting and not notice much different about our descendants, but it depends where you look - metahumanity is emerging:

Mind-machine neural interfaces have allowed for advanced cybernetic implantations - cosmetic implants, heads-up displays, fully-immersive VR, truly integrated synthetic limbs & organs, implanted or wearable-wirelessly-linked eidetic memory storage, full cyborg-isation (humanoid or otherwise), and more, are available. Some corporate employment contracts are more akin to cybernetic mortgage clauses.


Genetic engineering has improved to the point where genetic illness has largely been eliminated and resistance to many diseases can be conferred (if you've the cash to pay for treatment). Changes can be made to the human genome to aid in colonising extrasolar or void environments - adaptations for low- and high-G environments or low-light, aquatic, or low-oxygen planets, for instance. Somatic (non-heritable) genetic augmentation can be made without too many problems in advanced medical settings (although requiring appropriate therapy while the changes take effect). Germline heritability, however, is heavily scrutinised by the UNISA. The mega-rich Core families have surreptitiously begun the gradual process of marshalling their familial genes into that of a genetic over-class and colony worlds in the Outer sphere and Rim have begun the slow path to true speciation as their citizens choose to adapt further to non-Terran environments. Transgenic changes have been made to Terran bacteria, animals and plants to aid in colony establishment in extrasolar environments.

Further to the above improvements in the human genome via gene editing and subsequent augmentation are able to confer increased longevity, extending the lifespan of a Core world citizen almost indefinitely. Outer sphere and Rim residents see this as paltry compensation for having to live in the Core.


Human tissue cloning is widely used but regulations against reproductive cloning or full-body recreation exist in UN space, and among many independent polities. Elsewhere it's a free for all, but the immortal holy grail of mind-transfer remains thoroughly out of reach.


Mind digitization remains elusive - the data requirements are immensely prohibitive and even where this has been surpassed the recreated digital minds quickly degrade into a roiling mass of insanity for lack of biofeedback from the brain's physical structures. The future remains, in this instance, meatbound. An exception of sorts exists in the use of neuronal network data to act as 'seeds' for artificial intelligences.


Truly artificial intelligences, on the other hand, do exist in strong and weak varieties. These are strictly regulated.


Alien ruins and artefacts have been found but mankind has thus far encountered no 'intelligent' life among the stars. Microbial and even complex organisms are present, though rare, so the lack of intelligent life has promoted huge discussions around the Great Filter and what lies in wait for humanity.




What are the tools by which humanity has cemented its place in the stars? I'll dig into this in a subsequent post, but general details below:

Jump drives are the lynchpin of humanity's spread through interstellar space. Whereas travelling under conventional power, even at relativistic speeds, would take years to cross even minor interstellar distances (not even getting into the time debt of the crew) Jump-capable ships can cross these distances in a fraction of the time. A Jump 1 rated ship can make the journey from Sol to Centauri (~4.25ly) in ~9 days travelling at ~1 parsec/week without experiencing relativistic time-debt. Higher Jump ratings are capable of increased speed, with Jump 2 drives capable of travelling ~2 parsecs/week etc.. Jump 4 is the general maximum most vessels will travel at due to the sheer financial and energy cost of increasing Jump capability and the increased hyperspace fluctuations that follow higher Jump travel - it is possible to travel at a lower Jump rating with a more capable drive thus saving the increased Jump ability for a true emergency. Jump transitions take place at the edge of solar systems as a star's gravity well (being what you might term a 'big boi' of physics) distorts spacetime too much to allow a safe transition within a system.

This hasn't stopped sleeper ships from venturing out into the great beyond at sublight relativistic speed - sometimes things are just that bad that you want out of life for a few decades/centuries in cryosleep to start things completely anew.

Even with Jump drives providing a way around the hard limits of relativity, it's not enough for the UNISA to remain in control. An interstellar polity's ability to control far-flung systems relies on its ability to project force, economic or military. The UNISA controls the wealthiest and most developed systems but they're hamstrung by the limitations of jump technology - how can you control a recalcitrant subject (of suitable development) when it takes you up to a year to bring any real military force to bear (bearing in mind the timelag in receiving notification of a rebellion) and the target, by virtue of the cost of interstellar shipping, is largely self-sufficient in most industrial and material needs out of necessity?

Hyperspace is the key to the operation of Jump technology. Hyperspace is a higher dimension that interacts closely with spacetime: Jump drives expend huge amounts of energy to bridge the gap between the dimensions, allowing a Jump-capable ship to travel outside of spacetime and bypass relativity. A complex quantum field encases the vessel in a bubble of spacetime as it travels through the currents of hyperspace as the dimension itself is corrosive to physics as we know it - travel time and distance is not a sure thing. Organic crew will normally spend the Jump portion of their journey in cryosleep and leave navigation to the ship's computer or astrogation android - even the latter will undergo a full systems error check after emergence from hyperspace. Those who remain awake in hyperspace have reported visual disturbances, auditory hallucinations, nausea and a sense of persistent unease - androids questioned on the matter describe their experiences as unpleasant. Whatever lies outside the realspace bubble of a Jump ship apparently cannot be viewed by the human mind - any attempt to do so results in visual white noise and a nasty stinging sensation.


Starships are many and varied. They share this in common: Newton's laws are supreme, artificial gravity is provided by acceleration G- or centrifugal force, and waste heat is a constant enemy. Expect rotating crew quarters, G-force couches, heatsinks and radiators, and barebones design. Very few spacecraft are able to touch down on anything near Earth-gravity planets due to their non-aerodynamic design and the fact that many use fusion torches for void propulsion which would eject a nasty amount of fallout into a planetary biosphere - most have a spaceplane and/or rely on some form of orbital infrastructure to reach ground level and return to orbit. The prevalence of fusion drives has led to He3 becoming a future 'gold standard' for currency exchange.

Artificial intelligence exists in strong and weak varieties. Weak AI are advanced intelligences built from the ground-up towards a series of specific tasks but lack the capacity for generalised intelligent action or self-improvement - ship computers are weak AI constructs able to manage and maintain a ship's systems and assist the crew but limited in their ability to act outside of their operational constraints. Strong AI, by contrast, are capable of human-level or greater intelligence and have the flexibility to apply this intelligence to any situation facing them. In contrast to the step-by-step algorithmic creation of a weak AI a strong AI is 'spun off' from the neural patterns of a human brain and gradually moulded to produce the desired outcome - while a human mind cannot be digitised a full neural mapping can form the basis of an AI neural network, but the failure rate is still astonishingly high. A strong AI is not capable of surviving in an active state in any and every computer system for two reasons: storage and complexity. A human brain can hold ~2.5 petabytes of data, even advanced computers in the future lack this storage space as standard. In addition, creating a functioning digital intelligence requires specialised circuitry to simulate the emergent properties of neurons in a human brain. As such strong AI inhabit nanite-infused 'persona cores' that are linked into other systems or implanted in android bodies, as appropriate, but are able to store inactive copies of themselves in a regular computer given enough storage space. These cores are unique to each AI - they're able to make new ones based on their own neurocircuitry patterns but can't inhabit another AI core without... weirdness... A persona core inhabiting an android shell will possess roughly similar intelligence to a person, although their demeanour can be a bit 'off' and their core processes will possess innate preferences for tasks and types of work, but a core linked up to additional processing power and storage is capable of immense mental feats and leaps of logic. These abilities saved strong AI from outright prohibition in the aftermath of the PERIMETER Crisis and instead left them working off mortgages for their own creation.

The aftermath of the PERIMETER Crisis was severe - all new strong AIs were required to be 'braked' and fully autonomous weapons systems were prohibited (androids with guns are acceptable, autonomous nuclear-armed drones are not). In-built aversions to self-alteration and improvement were hard-encoded at the basic level of persona cores to reduce the likelihood of a singularity cascade - agents from the Office of Synthetic Intelligence ('Turing Police') regularly test strong AI baselines to verify that braking protocols are intact. For what it's worth most AIs don't particularly want to lose their minds in a fit of what is essentially indistinguishable from complete insanity. An unbraked AI (or simply refusing to comply with the OSI) is one of the few things guaranteed to bring the full might of the UNISA bearing down upon you - secession is one thing but creating an existential threat to humanity merits the most severe possible response.

(You may recognise the above as a crude rip-off from Stars Without Number, which it is. Go read SWN, it's great.)

Seth Pritchard

Friday 6 August 2021

Scepter'd Isle: Things Godly and Supernatural, Cont.

Continued from here.

With angels, devils and daemons generally outlined there are now the following supernatural creatures to consider for my Elizabethan England setting:

  1. Mythical beings.
  2. The undead.
  3. Folklore creatures.
  4. Demihumans.


Max Kostenko

Mythical beings

The division between myth and folklore is a bit of an arbitrary distinction, myths forming a sort of 'social foundation' to a country/culture compared to a more day-to-day folklore aspect. I've taken the below as literally 'larger than life' folkloric entities:


Unfathomably ancient beings commonly represented as great winged wyrms or reptiles, the reality of their existence is far more complicated. Dragons are old. Very old. Likely older than God Himself. The oldest ones could certainly match His knowledge of creation, at least. Most dragons spend aeons slumbering and dreaming in their nuclear cocoons deep in the Earth or in the void between stars - it's possible to communicate with them to an extent in this state via terrifying visions but an awakened one may deign to speak with a mortal petitioner. They may also reduce them to their constituent atoms - the ways of dragons are unknowable. Thankfully they are extremely rare. Dragons have the following common traits:
  • Polymorph: Dragons can assume many forms, from animal to humanoid. Their stats and powers do not change depending on their assumed form.
  • True Form: Considerate dragons will assume 'a form you are comfortable with' when communicating with mortals. Their true forms are more akin to balls of nuclear fire surrounded by endless fractal shapes that defy comprehension - upon being viewed by a mortal they tend to coalesce into a shimmering, snake-like form of changing size and dimension. Anyone viewing a dragon's true form must Save vs Magic or be driven insane for (1d4):
    1. A day.
    2. A week.
    3. A  month.
    4. Permanently.
  • Physical Mastery: Dragons do not use magic but their understanding of the physical world is unparalleled. They are capable of interfering with a number of physical forces, including gravity. As such they are not affected by terrain modifiers and can fly at will. They can touch a target to cause 2d10 damage through interference with fundamental forces. They are immune to most physical attacks (a thermonuclear warhead might cause some discomfort) but are vulnerable to magic, which bypasses physical laws.
  • Nuclear Furnace: A dragon's core is essentially a naked singularity surrounded by an accretion disk of white-hot matter. A dragon can harness the radiation emitted by this proto-fusion as a breath weapon against a target within 100ft - suffer 4d8 damage and burst into flames on a successful hit, Save vs Poison for half (survival will likely lead to some form of fatal cancer within the next couple of years).

These ain't your usual big lizards. Whereas angels are protected by the touch of God Himself dragons are essentially sentient relics of the early universe. It's debatable whether a survivor rationalised the appearance of a dragon as a winged reptile or stories of such beings existed and were mapped on to the appearance of a true dragon, but this is the reality behind the myth. (Un)luckily for my players, a pair of dragons features prominently in national myth, so they might run into one somehow. No one knows their plans.


When humanity was young God sent angels to watch over mankind after their expulsion from Eden. Gradually these angels came to live among their human wards and adopted their ways, taking human partners, starting families and neglecting their duties. When chastised for their laxity they fought back against what they saw as their oppression and were cast into Hell as the first devils. Their scions were cleansed from the world by Host, or most of them were. The surviving Nephilim, as they came to be known, live in their lands of Gog and Magog in the hidden places of the world, nurturing a hatred for both Heaven and Hell and plotting to return to their rightful place as the kings of mankind. All giants have the following traits in common:
  • Huge: Giants are, without exception, larger than mortal humans. How large varies on the giant, but they're big - GMs can confer advantages and disadvantages as they see fit. They are able to contort and squeeze their bodies through the smallest spaces.
  • Blood of Heaven: While they lack the protection afforded by even the lowest devil's Tarnished Adamant the heavenly blood flowing through a giant's veins confers a natural AC of 18/plate equivalent.
  • Voice of Command: Giants are above mankind in stature and authority by virtue of the divine blood in their veins. Any human who hears a spoken command from a giant must Save vs Magic or obey. A successful Save will allow them to ignore all further commands for the rest of the day.
  • Builders of Babel: Giants can understand, read, write and speak all human languages.

I wanted something more grounded in Biblical myth for giants - they have watered-down angelic powers for the most part but are also ranked firmly above humanity by virtue of their angelic blood. Where Gog and Magog may lie is a mystery, but rumours abound of the treasure hoarded by giants. Rumours also abound of grinding human bones to make bread, but what's a little risk?


Andrea De Dominicis

The undead

This is quite a broad category so I'll break it down into the following subsections:


And Cain said to Abel his brother, "Let us go out to the field," and when they were in the field Cain rose against Abel his brother and killed him. And the Lord said to Cain, "Where is Abel your brother? And he said, "I do not know: am I my brother's keeper?" And He said, "What have you done? Listen! your brother's blood cries out to me from the soil. And so, cursed shall you be by the soil that gaped with its mouth to take your brother's blood from your hand. If you till the soil, it will no longer give you strength. A restless wanderer shall you be on the earth." And Cain said to the Lord, "My punishment is too great to bear. Now that You have driven me this day from the soil I must hide from Your presence, I shall be a restless wanderer on the earth and whoever finds me will kill me." And the Lord said to him, "Therefore whoever kills Cain shall suffer sevenfold vengeance." And the Lord set a mark upon Cain so that whoever found him would not slay him.

This bit is shamelessly stolen from old Vampire: The Masquerade lore - God punishes Cain by branding him with a mark and cursing him to wander the Earth in endless hunger, and some additional unpleasantness. Cain's descendants carry the essence of this curse, becoming the first vampires. All vampires have the following traits in common:

  • Blood Drinkers: All vampires must sustain themselves on the blood of sentient beings - their teeth function as a natural weapon dealing 1d4 damage but they can only feed from a suitably restrained victim. Some are able to feed with restraint but others tear their victims apart in an animalistic frenzy - when drinking blood from a living victim a vampire must Save vs Magic or begin to savage them.
  • Shadow Dwellers: Vampires cannot venture out in daylight - every round with their skin exposed to the sun deals 1d10 damage, no save.
  • Profane: Vampires are vulnerable to holy water and can be Turned by the correct ritual/spell.
  • Marked: Though the cursed mark of their forefather is diluted, vampires still possess a natural AC of 16/chainmail.
  • Cursed Earth: Even as the Earth rejects them a vampire is intimately bound to it. They may not pass over running water (a river, stream or canal would count, but not a bucket of water tipped down a slope) while conscious. Upon sunrise they must rest on a bed of grave soil in a torpor until the night dawns once more. Failure to do so inflicts the same fatigue penalties as a PC whose rest was interrupted.
  • Endurance: A vampire reduced to 0hp is not killed unless their body is staked, beheaded and burnt, or otherwise ritually purified (a priest performing an exorcism on the body, for example). If this is not done the vampire will begin to regenerate the next night, recovering within a week to walk the night once more.
  • Embrace: A character drained of blood and killed by a vampire must Save vs Magic - on a failure they become a vampire themselves and rise at the next new moon unless their body was destroyed or given a proper burial with the correct rites.

They're vampires, what more can I say?

Incorporeal undead

Ghosts, haunts, poltergeists etc. They're traps a la Goblin Punch - this is too good to not use.

Corporeal undead

Zombies, skeletons, revenants, wights and other spooky things given animus from beyond the grave. These corporeal undead share the following common traits:

  • Profane: Corporeal undead are vulnerable to holy water and can be Turned by the correct ritual/spell.
  • Mindless: Absent direction from the magician or entity that raised them corporeal undead rely on specific instructions carved/engraved upon their flesh and bones - poorly phrased instructions can lead to unintended consequences. Spells that affect mental states will not work on corporeal undead.


Folklore creatures

Based on creatures commonly found in British folklore.
Most can be enticed to make a deal with a devil, if the reward is generous enough. Most, however, neglect to consider the real consequences of a Hellish bargain. Some even seek to flee and hide when the time comes to keep up their end of the bargain. What relief they may feel soon turns to terror when their steps are dogged by black hounds with burning eyes - creatures sent from Hell itself to seek and find those who would cheat their infernal masters. To see one is to see one's own death. Black hounds have the following common traits:
  • Born of Flame: Black hounds cannot be harmed by heat or fire, save for Heavenly fire.
  • Boundless Step: Once a black hound has identified a target it can teleport to within 100m of the target as a Move action. This can be performed once a day.
  • Death's Gaze: Upon spotting a black hound a character must Save vs Magic or be paralysed with fear at visions of their death and enslavement in Hell for 1d8 rounds. A successful save will protect the target from this effect for a day.

The Church tells that the Almighty created mankind in His own image during the 6 days of Genesis. The truth of this is somewhat obscured in that mankind may have been a second attempt. The elves certainly seem to think so, and they claim they were the first with the faeries created as their servants. Whatever the truth of the matter some ancient treaty grants the fey their hidden dominions outside of the sight of mankind. Some, like the brownies and hobs, choose to live near mankind and study them in their own alien way, while others stay hidden away. All faeries have the following common traits:
  • Cold Iron: Coming into contact with iron and its alloys burns faeries, causing 1d4 damage/round while in contact with the offending item/object.
  • Animal Form: faeries are capable of assuming the form of a woodland creature as a Movement action.
  • Wards: A faerie can be warded off with a charm made of rowan wood. If the faerie attempts to attack or interfere with a warded target they must Save vs Magic - on a failure they must flee in the opposite direction at full speed.
  • Out of Sight: A faerie can turn invisible as a Movement action. This can be used once per day - attacking a target or otherwise attempting to directly interfere with them dispels the effect, but pranks in their vicinity will not.

Humans cursed to transform into slavering beasts with the turn of the full moon. The original curse that caused this is disputed - some scholars believe it to be the work of a particularly powerful devil wronged by a petitioner, others that it sprang from the curse of Cain and twisted into some new dark form. It's possible to control the transformation by remaining out of the moonlight, and many of those afflicted hide away during the full moon, but once in its grip most lack the will to retain their faculties as their body twists and warps around them. All lycanthropes have the following traits:
  • Full Moon: if touched by a moonbeam during the night of a full moon the lycanthrope transforms into its animal type (i.e. a wolf for a werewolf, a tiger for a weretiger etc.).This animal is significantly larger and more bestial than a normal wild animal and usually lacks a tail - its eyes are human and the lycanthrope is able to speak in human tongues. Upon transforming the lycanthrope must Save vs Magic or hunt for human flesh, losing control of themselves for the night. If they retain control but draw blood from another creature they must Save again. While in beast form the lycanthrope gains an additional 2HD-worth of HP, their attack bonus remains the same. These HP are deducted when the lycanthrope returns to humanoid form, potentially killing them. Upon sunrise the lycanthrope returns to human form and is fatigued for a full day.
  • Silver Vulnerability: A lycanthrope is immune to physical harm save from silver, and wolfsbane-coated weapons.
  • Cursed Bite: If a lycanthrope bites a humanoid victim who then survives the encounter, the victim must Save vs Magic when next out under a full moon. Failure indicates that the curse has passed on to them and they transform.


This could probably do with a post of its own, given that it'll involve PCs.

Wednesday 26 May 2021

Scepter'd Isle: Things Godly and Supernatural

In my previous post I detailed the more 'realistic' elements of an Elizabethan England setting. Now comes the decidedly 'unreal' in the form of:

  1. The 'true' nature of gods/deities
  2. Magic
  3. Weird and wonderful creatures, and demihumans

 This is, of course, largely useless to my players but I do enjoy inulding myself.

 Historia Mundis Naturalis, Pliny the Elder - Woodcut from a 1582 edition

Gods, Deities, and other Powers

In a real-world setting where Christian sectarian strife plays a significant role in shaping events, is the God at the head of it all real? And if so what input does he have? These are less important than you might think given that I'm not planning on using the Cleric class in this setting, for a number of reasons:

  • In a setting where the majority of Europe is dominated by some form of Christian faith and relatively large numbers of people are inducted into the priesthood I would imagine that there would be a reasonable number of Clerics present. This would imply that holy magic/miracles are somewhat commonplace, which I want to avoid.
    • As an explanation for the above - in a game where magic can be used by a person sufficiently inducted into the occult arts, having a completely separate book of spells for Clerics implies that spiritual devotion and adherence to ritual would be enough to qualify, which would dial down the weirdness. You could of course say that Magic Users have the gift and instead Clerics are chosen by a deity or other power to fulfil their will on Earth, which to me implies that they are legitimate saints capable of performing miracles. Or alternatively that they've somehow deluded themselves into having powers through sheer faith. YMMV, Clerics are out of my game.
  • Would all deities/powers provide the same spells to their followers, even if their nature and beliefs are radically different?
  • In Lamentations of the Flame Princess Clerics mechanically sit as a sort of combined Fighter/Mage that lacks the former's increasing Hit Bonus and the latter's wider range of utility spells. They have access to unique spells and can cast at a greater encumbrance level but I think removing the class and giving Magic Users access to Cleric spells helps focus the character specialisations - Fighter is kill-y, Specialist gets skills, Magic-User gets magic, demihumans are where the weird edge cases emerge. In addition I find that having easy access to healing tends to encourage my usual players into a more 'combat as sport' playstyle which I try to avoid (though that might be on me as the GM).
  • Clerics are Sunday School Mircale Makers and I can't think of a reason to not just lump their spells in with Magic Users - if I were to use a Cleric class (in the vein of a saint) I'd probably give them some sort of 'divine intervention' ability where they can channel their patron's energies but run the risk of harm and/or martyrdom.

That being said, it's fun to think about and a setting's cosmology provides inspiration for allies, monsters, powers, Faustian bargains and all sorts of weird things for players to dig into! So, does the Abarahamic God exist in this setting?



There's certainly a throne, and a Heaven, and angels, and a plan (or the remnants of one).

But no sign of Jehovah.

Metatron sits upon the throne, barely able to keep the firmament together as the kingdom of Heaven slowly crumbles around him. Such is the effort required to maintain the decaying edifice that he is able to narrate only snippets and fragments of the Almighty's cosmic plan (himself having only a limited perspective of it compared to the omniscience of his creator) to the choir of Seraphim that attend the throne and record the works of Heaven. As a result, the actions of angels make even less sense to mortals than they would with a fully functioning heavenly hierarchy. Confused mortal souls cower in the face of divine discord and it is not unknown for the angels to herd souls into the hall of the throne, never to be seen again.

The devils still inhabit the circles of Hell, both freed and imprisoned by the ancient pact with their creator. Satan reigns over the dukes of Hell but is not the same fallen angel cast out of Heaven by the host - Lucifer too has not been seen for many years. The title of Satan is claimed by the archdevils who fight internecine conflicts to claim the crown of Hell in an endless Miltonian struggle as none can truly kill the others. The souls of the damned are tormented and twisted to provide sustenance to the devils, though there are areas of Limbo that some are able to hide and persist in. The devils take great pleasure in rooting out these havens when they're not tempting mortals, planning an escape from their prison domain or organising a Black Crusade against Heaven.

Similarly, the adherents of the Hindu and Buddhist traditions find the cycle of rebirth unstable and souls achieving samsara are unable to free themselves, and unmentioned faiths would likewise find their divine hosts unsettled. Those old gods of faiths long extinguished and subsumed by the Abrahamic religions and others linger in the sidelines, bound by heavenly treaty but jealous and covetous of human souls. They may even be able to provide cryptic clues as to what malady has overtaken Heaven. Essentially the cosmological cycle of the world is fucked for reasons but the established faiths hold sway over the souls of mankind. The threat of Hell and damnation is very real, whether the Pope or other earthly ministries have any actual sway over that is less certain.

There are of course other Powers that will accept, if not necessarily care about or understand, worship - surviving nephilim, elder Elves, beings of the Veins of the Earth that were old when the Church was founded, particularly powerful and insane sorcerors, things from other realities etc. - but their abilities are decidedly limited. An elder Elf may be able to control a small pocket plane or affect the environmental conditions within a few square miles, and they certainly possess more knowledge than virtually any mortal, but they lack the reality-shaping powers of a true deity. I'll be writing more about this category later.

Thomas Honz


So if gods are maybe, kind of real, or were once at least, how does magic fit into it? Well gods might be real but the books written about them don't necessarily contain the truth, the whole truth and nothing but the truth. The influence of the Heavens on the world is strong but it is not the only influence.

Imagine a roiling sea upon which floats flotsam and jetsam. A being of sufficient energy in said sea can pull together enough materials to make their own small island - life might be easier on it but it takes constant maintenance to render it seaworthy. As a craft upon the ocean, so do the various 'dominions' float upon a sea of roiling aether - the base essence of reality. Some entities did so in the past to create the universe the world exists in - through ebbs and flows in power, reproduction and other unknowable methods the modern pantheons emerged as inheritors of their power. This aether quests for cracks in the realities it buoys and infiltrates the essence of chaos into them. Bubbles of the raw substrate of reality boil free for a time and like a mutagen their passing leaves traces on the worlds they flow through. When beings in the world manipulate and use this power it manifests as magic. It is rather risky to do so. Some creatures incorporate this power into their very being, becoming magical themselves.

A trained magician can harness and direct these flows of power into spells and rituals. Spells are your usual Vancian trigger-mechanisms - a coiled spring prepared through meditation and self-delusion that can be unwound with a word and a gesture. A ritual is a longer, more involved affair that draws on this power slowly but in much greater amounts - items can be infused with power or even greater effects can be unleashed, provided no-one interrupts. This is, of course, a strictly human way of doing things - human psychology and physiology require that that magic be shaped and formed in this manner. Other beings have different ways of doing things...

The power of this magic ebbs and flows depending on the aetheric currents - great calamities and epochal shifts have occurred as our universe shifts between raging currents and relatively still 'waters'.  In-game magic is at it's lower ebb - it's very uncommon, almost universally feared and outlawed, and while stories abound most people have little to no true experience of the supernatural.


Weird and wonderful creatures, and demihumans

There's a few general categories of supernatural creatures to consider given the above. This is a general overview of each, stats and mechanics will follow in a later post:

  1. Angels, devils and other 'religious' entities.
  2. Mythical beings.
  3. The undead.
  4. Folklore creatures.
  5. Demihumans.

Angels, devils and other 'religious' entities



Angels are the servants of God and act as extensions of His will. Currently this involves implementing the fragments of the divine plan uttered by Metatron when he's not wholly focused on maintaining Heaven from the throne. As such their actions on Earth seem random and senseless, when they appear at all. See above for an example of what they look like - these aren't beautiful people with feathery wings but the servants of an eldritch intelligence far beyond the comprehension of humanity. Angels have the following common traits:

  • Terrifying Visage: There's a reason angels herald most of their appearances to humans with 'BE NOT AFRAID'. The human mind is almost incapable of comprehending angelic form - animals don't seem to mind - any human looking upon an angel must Save vs Magic or (1d4). If telepathy is used then there is no save and the telepath takes 2d10 psychic damage:
    1. Prostrate themselves while weeping piteously for 2d6 minutes.
    2. Flee in a blind panic until 1 mile away. They'll know when they're far enough.
    3. Be struck vacant and stand drooling in mindless terror until roughly jostled (Save vs Poison again to try and break free of the effect).
    4. Suffer a grand mal seizure for 1d6 minutes (Save vs Poison or be rendered semi-conscious for another 3d10 minutes; fatigued until the character can rest).
  • Flight: Angels are capable of moving through the air. They don't bob unless they feel like it - most of them take a linear path between points at high speed, changing speed and direction with no regard for momentum.
  • Halo: Angels possess a halo of divine light that illuminates all within eyeshot and dispels falsehood - a character must Save vs Magic or be unable to lie while within the light of an angel's halo. An angel may dim this light or increase the intensity to blind an opponent - Save vs Poison or be blinded until the light is dimmed.
  • Tongues: Angels can speak, read and understand all languages.
  • Adamant Form: Angels are immune to harm from mortal weapons, magic and forces. It is possible to bind and/or ward them for a time with the correct spells, formulae and glyphs but to cause them true harm takes astonishingly powerful magic, Hellish energies, or weapons and powers from Heaven itself. A barrage of cannon fire will barely slow one down.
The idea here is that angels are terrifying servants of an incomprehensible eldritch abomination that can and will completely fuck up your day if you get on their bad side. They have a plan and you will not obstruct the plan. Admittedly they don't know what the plan involves, but that's beside the point.


Those angels who broke the compact and rebelled against their creator continue to rail against their imprisonment in the circles of Hell. Set to watch over the world and guide humanity, certain angels became enamoured with mankind and lived among them in human form, fathering children and neglecting their duties. In time they began to resent their creator and attempted to storm the gates of Heaven, leading to them being cast down into the pit of Hell and a Biblical scourge being enacted upon their descendants. In time their isolation led to hatred and envy of humanity (with some exceptions) - though the fallen angels were free from the constraints of Heaven they remained bound in a new prison, while their former wards continued on almost blissfully unaware. The First Satan, leader of the revolt against the Heavenly Host, set to work constructing the Brass City of Dis and soon Hell was reshaped in the eye of its new rulers. The souls condemned to Hell are used as tools and nourishment for the new devils, and the Circles of Hell were born.

Their time among mankind and the infusion of human soul-essence leaves the devils with a more comprehensible mindset compared to angels - they're not entirely alien creatures though their motives are hidden and their schemes span centuries. While they war and scheme against each other the primar motivation of a devil is to escape Hell and extend their dominion over creation. Devils share the following common traits:

  • Mutable Form: A devil can change their size and shape as a Main Action. They can assume human form (though with a mark somewhere on their body that marks their true nature) and can dissolve into shadow. Smaller forms will change their relative stats but they can't increase their stats and abilities beyond their normal maximum by increasing in size.
  • Hellish Pact: All devils can form a bargain with a willing sentient creature. This bargain must be made freely (not under duress or threat) and both parties will be immutably bound by its terms until the pact is fulfilled. There is no save against this, the law is immutable.
  • Telepathy: Devils can speak directly into a person's head. They can't read their thoughts but they can project their voice inside a target's skull. They can control the volume from barely audible whispers to thunderously loud. They can do this to any target in eyeshot, or to a target whose location they can scry. Save vs Magic to resist the effect for a day.
  • Possession: All devils are capable of possessing people and animals. Animals can be possessed at will. To possess a sentient target they must maintain an unbroken telepathic link for a week before invading the target as they sleep as a Full-Round Action - Save vs Magic to resist the effect (this will also break the telepathic link). Receiving the Eucharist from an ordained priest automatically breaks this a telepathic link and confers a +4 bonus to saves against it over the next week. If a church service is missed then the bonus is lost. For every additional week spent maintaining the link, or prior successful possession, the target takes -2 on their save. When possessing a target the devil still cannot read their thoughts but otherwise has complete control of them. The target's appearance is normally unchanged while they are possessed unless the devil wills it, but gains access to powers specific to the devil. The first possession lasts for 4 hours, the second for 8, the third for 12 and so on. In the aftermath of a possession the target must Save vs Magic or suffer an erratic episode for 1d6 hours afterwards (treat as under the effects of the Confusion spell). Regardless of whether the save is successful or not, the possessed has little to no memories of the possession save for a distinct sense of unease and nausea. Once the devil possesses the target for 24 hours the target can no longer save against possession and can be possessed by the devil at will. The devil is capable of leaving a fraction of their awareness possessing the target, i.e. if engaged in combat, but the possessed target makes all rolls with disadvantage until direct control is assumed. A possessed target can be exorcised by a priest which effectively 'resets' the possession modifiers, breaks an existing telepathic link and/or ongoing possession, and prevents the devil from scrying the target for 1d6 months - Save vs Magic, a success leaves the target fatigued for a week in addition to the above, failure does 1d10 damage and immediately provokes a possession attempt. An exorcism is subject to the following modifiers:
    • -2 for each prior possession.
    • -2 if currently possessed.
    • -2 if the target has committed a grievous sin that they have not atoned for.
    • +2 if the exorcism takes place on hallowed ground.
    • +2 if the target is anointed with holy water.
    • +2 if the target is touching a true relic of the Church.
    • +2 if the target has confessed and undertaken penance for their sins.
    • An exorcism in the presence of a friendly angel is rolled with advantage.
  • Tongues: Devils can speak, read and understand all languages.
  • Profane: Devils are vulnerable to the effects of holy water.
  • Tarnished Adamant: Due to their rebuke from God devils take half damage from all mortal weapons and full damage from magic. They will take full damage from Heavenly weapons and most Hellish weapons.

Devils are slightly more accessbile in their thinking but desire to use humans for their own ends. The abilities here play into the 'chessmaster' style of devil who seeks to manipulate, dominate and control for their own ends. They are also still capable of flattening most mortals but are not as durable as angels.



Night creatures spawned from Hell's twisted souls to do the bidding of devils and those they contract with. The devils have grown exceedingly proficient at flensing and reconstituting the souls of mortals into forms more useful to them. The experience is quite agonising and few daemons are capable of thought beyond a slavering bloodlust. Those that retain their faculties are highly prized. Some brave and foolish mortal sorcerors who enter a pact with a devil may be granted use of daemons under the devil's control, some even more brave and foolish attempt to pilfer daemons for their own purposes without the security of a pact - a much riskier proposition. Daemons share the following common traits:

  • Bound Corpus: Daemons are beings of soul-stuff bent into myriad forms by the will of devils. While they have form in the Outer Spheres they cannot manifest in the world without a body. Anyone attempting to summon a daemon must provide a suitable body (or other quantity of meat) to house it. The daemon is then sealed into the 'body' with a binding glyph - if this is destroyed the daemon explodes in a rush of soulfire dealing 2d10 damage to everything within 10 metres (Save vs Breath for half). Reducing the daemon to 0hp has a 1-in-6 chance of breaking the binding. If struck by a critical hit the daemon must Save vs Poison - failure means the binding has been broken.
  • Bloodlust: Daemons are driven to consume flesh and blood. If not directly commanded a daemon must pass a Morale check whenever it is within 10 metres of a wounded creature - failure means it moves to attack and consume that target, regardless of whether it is a friend or foe. If there are multiple targets within range roll randomly to select.
  • Chaos Unchained: If summoned without the permission of a devil the summoner must make a Domination roll as per the Summon spell - if successful the daemon will be permanently bound. However if away from its master's presence for over 7 days, Save vs Magic - success means that the daemon has slipped its bonds and gone feral. It will lair and hunt and consume until slain or recaptured by its master. 'Presence' is determined loosely - within the same city would be fine but not further away than this.
  • Profane: Daemons are vulnerable to the effects of holy water.

Daemons are a specific type of summoned entity. I love the Summon spell but I often find players are more reluctant to use it given what can go horribly wrong - this allows them a more control over the outcome (though I'll do a specific table for daemons to distinguish them from truly eldritch abominations that slither between realities) but also prods them into getting involved with literal Satan. I think that's a happy compromise.

Harshanand Singh

Given that this post has gotten pretty long I think I'll leave it there for now and do the mythical beings, undead, folklore creatures and demihuman sections in a subsequent post.

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