(Star)Ships for a Lava Sea, part 2

This series of posts began in August with a post entitled “Starships in Crowfield.” Despite the title, that post was really about beasts of burden.

With your feedback the idea grew and mutated until it became ships floating on a lava sea. This post is about some rules to create such ships, and to conduct ship-to-ship combat. The rules here are modified from rules I wrote a few years ago to develop starships.

We’ve come full circle. We now have “starships” in Crowfield.

Priorities

The first thing I need to tell myself is that “it’s a game.” The priorities are enjoyment and ease of use. Detailed realism is not a goal. Ship design will be intentionally abstract.

In Traveller the various components of a spaceship were rated in how much volume they occupied. Nothing else mattered. It was simple, and fun.

In GURPS Space, the matter was more complicated: not only were components rated by their volume, but all by their mass, and power consumption.¹

GURP Vehicles made it even more complicated.

While the GURPS systems were more realistic they weren’t more fun.²

In fact, the best³ system I ever saw was Big Robots, Cool Starships for the Big Eyes, Small Mouth RPG. In that system, a ship is constructed as if it were a character. No talk of measurements or power consumptions. It’s nice and simple.

(As a testament to the ability of a professional game designer to write to what the boss wants, both Big Robots, Cool Starships and GURPS Vehicles were written by the amazing David L. Pulver.)

Size Matters

My lava ships will be comprised of “modules”

Each ship has a number of “slots” determined by its size. A slot is an abstract unit of space that can be filled with a “module.” Each type of module gives the ship different capabilities.

The smallest lava ship, the equivalent of a rowboat, is size 4. The next size up is 6, then 8, 10, and 12. If you looked at those and said “those correspond to polyhedral dice”⁴, then you either passed your observation check or you’ve been reading ahead.

Larger ships are possible: size 16 (1d2 × 1d8), size 20, size 24 (1d4 × 1d6), and size 32 (1d4 × 1d8) are all possible. I’m sure you get the idea. the only thing is that we try to avoid both dice being the same, which is why size 16 isn’t 1d4 × 1d4. A huge size 36 ship would be 1d3 × 1d12.

Modules

In Traveller 1 ton was 14 cubic meters, but in Crowfield modules are abstractions. There is no exact size. Some modules will be bigger than others, and some progress in a non-linear fashion.

As of now, I think that there will be ten types of modules. Three types are required, and the rest are optional.

Module	Required?	Description
Armor	No	A ship with no armor modules has an Armor Class of 10. Each armor module improves this by 1.
Cargo	No	This is “empty space” set aside to carry goods. Cargo space is less abstract, but it progresses in a exponential fashion. For example, a single cargo module would be big enough to carry a coffin, while four cargo modules will be the equivalent of a modern tractor-trailer’s 53-foot trailer. I will do a future post about this.
Carpenter’s Workshop	No	This is the equivalent of an engineering section. The Carpenter’s workshop allows you to have a ship’s carpenter as a crew member. The carpenter can make emergency repairs during or after combat or other catastrophic event.
Crew Quarters	No	A ship is assumed to have enough room for the crew members to sleep on the deck. If you want them to have nicer quarters, treat it as Passenger Accommodations.
Fuel	Yes	This is just a holding tank for water that’s used to hydrate the pushers. One fuel module will provide fuel for one pusher module for 7 days.
Fuel Filter	No	A fuel filter converts raw water into filtered water. One filter module can convert one fuel module’s worth of fuel in 4 hours.
Fuel Still	No	A fuel still converts filtered water into distilled water. One filter module can convert one fuel module’s worth of fuel in 8 hours.
Lava Levitation	n/a	Ships are assumed to made out of Teesha wood. A separate levitation module is not needed.
Passenger Accommodations	No	This will require its own post.
Speed ("Pushers")	Yes	The more Speed modules determine a ship’s speed factor, which is a simple percentage of the speed modules of the total modules. For example, a size 4 ship with one speed module would have a speed factor of 25%, and will take 4 hours to cross one hex. A speed factor of 33.3% would take three hours, etc.
Weapons	No	There are three types of weapons: ballistae, catapults, and rams. Each weapon module gives that ship 1 attack roll per round. Ballistae do get 1 damage roll if they hit. Catapults are -5 to hit, but score 1d4 damage rolls. Rams? Dunno yet.

Design

To design a ship it’s as easy as:

1. Pick a size.
2. Pick a module for each slot
3. Calculate:
   1. speed: (speed modules/size) × 100
   2. armor class: 10 + armor modules
   3. fuel duration: (fuel modules / speed modules) × 7 days
4. Fill in a design/damage sheet. For a “single die” ship, this is just a list from 1 to ship size. For a “two dice” ship, this is a matrix. For example, a Size 24 ship’s matrix might look like this:

Ship Name:	Sparrowhawk
Speed:	25% (4 hours per hex)
AC:	13
Fuel Range:	112 hours (28 hexes)

	1	2	3	4
1	Speed	Fuel	Fuel	Fuel
2	Speed	Fuel	Filter	Still
3	Speed	Armor	Armor	Armor
4	Speed	Ballista	Ballista	Catapult
5	Speed	Cargo	Cargo	Cargo
6	Speed	Cargo	Cargo	Cargo

Combat

Combat works much the same way as melee combat: “to hit” (including Crowfield’s custom defense roll) is much the same, but damage is different.

To-Hit

To hit is rolled by the weapon’s operator. In addition to normal modifiers, the following apply:

• Your ship is faster than the opponent: +2
• Your ship is slower than the opponent: -2
• Close range: +2
• Medium Range: ±0
• Far Range: -2
• Catapult: -5

Damage

On a successful attack with ballista (or equivalent, including a lightning bolt), the attacker rolls dice based on the defender’s ship. For example, the Easy Gold (Jalice’s ship) hits the Sparrowhawk from the Design section. So Jalice’s player rolls 1d6 and 1d4, Let’s say the 1d6 is a 5 and the 1d4 is a 1. We cross reference that on the Sparrowhawk’s matrix and see that it’s a speed module. The module is now damaged and out of commission until it’s repaired. Because the Sparrowhawk doesn’t have a carpenter’s workshop, it can’t be repaired during combat.

If the same module is hit a second time, it has major damage: permanent repairs will take days.

A third hit destroys the module completely.

If the hit was with a catapult (or fireball) instead, the player rolls 1d4, and makes that many damage rolls against the enemy.

That’s it

That’s it for this week. Next week or the week after I’ll fill in the pieces for the cargo and passenger modules. I might have left something out of the combat, too (like changing ranges!).

What do you think so far?

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1. To be fair, Traveller cared about power consumption, too. But Traveller’s method was much simpler: jump and maneuver drives were rated from “A” to “Z.” Your ship’s power plant needed to have at least the same rating as the higher of the other two. It’s so simple that I don’t count it.↩

2. Fun, like beauty, is in the eye of the beholder. When I say things like “this is more fun than that,” I am, of course, talking about my personal, subjective feelings on the matter. I am not making pronouncements based on absolute fun quotient. That is the job of Friend Computer.↩

3. Again, subjective.↩

4. I’ve never liked the term “polyhedral dice.” It’s redundant. I’ve never seen a die that wasn’t a polyhedron.↩