What sort of feel should I go for?

[Adam]

Great idea mate! You probably don't have to do it in so complicated a fashion, although the face down cards idea is good. There's probably some simpler way to simulate lack of knowledge of an enemy ship's armament... but at least you don't need to hide the army lists. A ship could have X number of weapon slots, each of which has options of profile Y1, Y2 etc. Like Tyranid hive fleet ships. It comes with one weapon in each slot automatically, so provided you've chosen statlines that are roughly equivalent in effectiveness, you can assign them the same points value.

E.g. Let's use a simple example. Using Ollie's drone/cruiser/asteroid setup, each weapon rolls a number of dice looking for a certain score on each one to cause damage. The weapons do different damage against different targets. For the same points value, you can ensure all the weapons do X amount of damage on average. These are presumably capital ship broadside batteries or asteroid ship weapon platforms, unless all the ships have large amounts of health. Dice are D6s, it's easier.

Nukes (spaceborne explosions = splash damage = lots of poor quality dice):
- Drones 6D6/4+ [avg. 3]
- Cruisers 6D6/5+ [avg. 2]
- Asteroids 12D6/6+ [avg. 2]
Lasers (precision):
- Drones 2D6/2+ [avg. 1.8]
- Cruisers 4D6/2+ [avg. 3.6]
- Asteroids 3D6/4+ [avg. 1.5]
Seismics (critical damage, escalates massively):
- Drones 3D6/5+ [avg. 1]
- Cruisers 4D6/4+ [avg. 2]
- Asteroids 6D6/3+ [avg. 4]

The average damage values for each total 7, 6.9, and 7 respectively. Assuming that the points costs will be such that an equal amount of points of drones, cruisers or asteroid ships will have similar resilience and degradation under fire, this is provisionally balanced (i.e. it looks balanced, but of course playtesting will tell).

[Peter]

Ships will be custom, once I've worked out the full details.

The current plan is for warships to use a category and level system, with the basic categories being as follows:

• Warrior. The mainstay of a group, warrior classes bear the brunt of combat, able to outmanoeuvre or outfight most enemies. Larger warriors have lower agility ratings than smaller ones.
  
• Defender. Defenders act as hospital craft, emergency point defence, and recovery craft. Most are modified warriors, carrying additional resources in order to compensate for the missing weapons which would give them away during a burn.
  
• Carrier. Carriers carry a squadron of 'runabouts'. These are versatile small ships which perform a variety of duties, including dropship and air support for atmospheric forces.
  
• Fortress. Virtually immobile units built on existing entities such as asteroids. Very hard to attack, because they suffer virtually no heating issues.
  
• R-Ship. A countermeasure to Fortresses which is almost impossible to implement, but lethal when used. It consists of a solid chunk of metal, a huge fusion drive, and a reckless disregard for heating issues. Its job is to hit relativistic velocities and 'forget' to skew-flip.

Very high level warriors can basically take on the role of carriers as well. They would mostly deploy scouting missions. After all, a powerful enough warrior is basically a one ship armada.

Asteroids are basically flying fortresses. Very hard to take down, incredibly well armed, but still potentially vulnerable.

This also features small craft, although they aren't very good targets under these rules.

For weapons, bear in mind that available weaponry will include nukes, kinetic weapons, R-bombs,

[Oliver]

...lasers, weird dark-matter things, seismic warheads that dock with the target, etc? actually thinking about it seismic warheads would be massively hard to pull off because they would have to match course with the target and then approach, making them sitting ducks for close-range attacks. Oh and here's an idea for R-bomb rules: it comes in from a table edge, at ridiculous speed, in a straight line, and if it hits anything, there is a Splosion and it just keeps right on going, such is its momentum. Unless what it hits is a planet. Of course, course corrections would be nigh-impossible, so you might have to eg. aim it at the start of the game or the previous turn or something. And then just fire when ready, for gameplay's sake.

[Adam]

"At that speed it didn't matter whether you'd been hit by a nova bomb or a spitball." - a well-known quote from Joe Haldeman's The Forever War, discussing relativistic attack drones. Ollie, your R-bomb rules are (again!) a great idea, but the drone would by no means keep on going. It would be destroyed utterly by the impact. Ships like that would explode if they hit a frozen pea floating in space*, never mind an asteroid. Of course, such a weapon would be very hard to aim due to the difficulty in steering, unless their velocity relative to other ships is high (eg. ordinary ships move at <0.1c, c being the speed of light; drones move at >0.9c as they do in The Forever War). The problem is, accurately representing them has them cause insane amounts of damage - total destruction to most ships, I would have thought - but be extremely unreliable, missing most of the time due to space debris. They would also be reduced greatly in power by chaff, because a single piece of chaff could destroy a drone completely, as above. Relativistic-moving shrapnel could still hit the target ship, but I suppose it wouldn't be that likely.

*Edit: Literally, to my knowledge. Unless of course Dragonlord and his physics degree say otherwise.

[Peter]

An R-bomb starts out as a 100 tonne almost solid chunk of metal moving at 0.75c, so it has the kinetic energy equivalent of its own rest mass.

Against any kind of spacecraft, that's an almost guaranteed kill, even against a Fortress.

I'm on the 'keep going' side here. It would break up, but it has easily enough momentum and energy to simply smash through absolutely everything it hits. It would also fatally irradiate anyone nearby, I suspect.

[Peter]

I just ran some maths, and it seems like if everything were to scale, a turn would be about four hours long.

That gives some idea of the scale of actual space battles, I think. A milimetre of tabletop represents a distance of around 10 light-seconds, and an acceleration of g would correspond to 2" on the tabletop, or 500 light seconds per turn squared.

Of course, this maths suggests that combat ranges are somewhere in the region of "base-to-base contact".

[Adam]

That could be pretty cool, when you think about it. Worth experimenting with, at least.

[Peter]

Just for anyone interested, combat range would generally be around 1 light-second, with detection range at 18,000 light-seconds for a ship chucking out everything it has.

I haven't checked the resolution for that, however.

[Peter]

I'm leaning towards tacking a 'science fantasy' label on the whole thing (again, if I'm not mistaken) -- while it could be seen as 'cheap', it doesn't mean I'm suddenly going to drop all pretence of realism.

What it does mean is that I have a nice explanation for faster-than-light travel -- using a Homeworld-inspired "FTL drives are a divine relic" rule, possibly with some arbitrary but interesting metaphor.

I'm also going to see what I can do as far as working out some very simple values for drive power and the power needed for particular weapon systems.

In particular, I want to check that particle point defences are 'cheap' enough to be worth including.

[Adam]

If you want particle point defences, have particle point defences. It's your game

[Peter]

Well, 120 MJ is probably overkill for a point defence, but it's a decent number. On the flip side... there are some problems with that.

The magnetic field required, for example, would probably not be pretty for living things.

[Adam]

You can always claim that it's an A-level physics question and you're simply modelling the bullets as particles. There's no air resistance in space anyway, it fits perfectly! (We ignore the buffeting effects of nearby explosions, spilled plasma, interstellar hydrogen, and the enemy's hull...)

[Peter]

It might actually be simpler to describe the whole thing as a circular railgun, firing special charged rounds.

If we assume 100 MJ ammunition, and that 10,000 rounds are fired per second (between the entire weapon system as a whole), then we have a weapon that uses somewhere around a terawatt. We'll be generous and call it 70% efficiency, which means that the ammunition has about 70 MJ of kinetic energy.

Given that that's probably not much more than a percent of a single craft's power consumption anyway, I don't see that being an issue.

We do need a projectile travelling at a not inconsiderable fraction of the speed of light, however, in order to have a decent range.