Hornet Twin Envelope Airship

In exploring enemies for the players to fight in their newly found flying saucer my first step is to consider the mechanist version of a flying vehicle. I need something less large than the ealrier gyrocopter and the aerostat from machinery to the max which is a full zeppelin.

Being a fan of the Mortal Engines books, I like the idea of slightly up armoured and sturdy airships (the movie was pretty but deviated a lot from the books). Some of the movies concept art is awesome though and very evocative. This one is particularly inspiring.

Mortal Engines concept art by Ian McQue

The new vehicle below is intended to be a template I can work off to create various custom fits for air encounters. In also experimenting with a new vehicle stat block.

The Hornet Twin Envelope Airship

This twin rigid envelope design aerostat is built for the rough and tumble life of a trader. While drawing on less advanced materials compared to visitor vessel its reinforced hull makes it sturdy, though unable to haul the comparable loads. The design incorporates powered fan systems into the 20-foot-long airframe allowing for rapid speed and manoeuvrability. The main cabin is small and cramped with a bunk and head towards the back that is enough to provide comfort for one, but discomfort for its crew of four.

The lift is achieved through airbags utilising pure air sourced from alchemists through their arcane practices. This ingenious element making the design more compact than mere heated air that more common balloons can provide. Pure air cost 12gp per stone and contains six parts of the concoction. When exposed to the envelope gasses the vehicle can fly and consumes 9 parts per day of operation. Overall, the envelopes can hold 30 stone (180 parts) of pure air giving it a 20 day operation period.

In combat the pilot focuses on steering the vessel and the passengers can operate the three arbalest turrets placed around the vehicle. These turrets mount massive steel bolt ammunition that is effective even against the toughest alien vessels.

The design itself is common enough that parts, fuel and used vehicles can be found in many major towns. When purchased used they often come with custom modifications and a shrewd merchant can snap up a deal. They can be built by a 5th level machinist at a +6 build penalty taking 39 days at a base cost of 32,375 gp.

Hornet Twin Envelope Airship (Huge Machine)

Crew: Passengers: NPC Crew: Cargo: Consumables: Cost:	1 (pilot) 3 passengers (can perform crew or gunner actions) As 9HD (BAT 3+; BST 12+) 100 st. (includes 90 bolts, fuel, passengers and cabin) 9 parts of pure air per day, 180 envelope capacity 32,375 gp
Armor Class: Hit Points: Move: Weapons: Abilities:	7 54 (VHP) 240’ (80’) 3 Stabilised steel rod heavy arbalests (1d8 VHP, +1 to hit, range 120’) None

Build Notes

The mechanist build for this vehicle is as follows:

Utility Airship

Hit dice: 9 (36 VHP, save F5, structural vehicle)

Armor class: 7

Move: fly 240’ (80’)

Weight: 810 st. (5.7 tons)

Carry: 405 st. (3 seated passengers plus one passenger cabin for 260 st.; 30 st. fuel, 90 bolts for 15 st., 100 st. cargo)

Attacks: 3 Stabilised steel rod heavy arbalests (1d8 VHP damage, +1 to hit, range 120’)

Positive abilities (total): Automaton immunities *, increased AC +2 ##, Increased move (flight +180’) * ####, Movement mode (flight, full hover, replaces ground) ###, passengers (4) ###, protected compartment ####, Ranged attack (15' multiplier) ###, reinforce structure *. (***** ###)

Negative abilities (total): Requires operator (mechanist or learned) *, Requires ammunition (Steel arbalest bolts, 4 gp each, 6 per stone) ####, Other negative ability (Requires pure air to operate, 12 gp per day) ####, Restricted movement (uncontrollable in strong winds) ####. (** ####)

Cost (net abilities): 32,375 (** #### ###)

Design elements

I restricted the weight and carry capacity but was shooting for a reasonable amount of hit dice. It needed this to be able to go toe-to-toe with a visitor scout. 9HD gives me a good weight allowance with solid health.

I added a full passenger to this design at 200 stone to represent a small cabin. This would be shared by two people at a time leading to a lack of comfort. With a crew of four doing two shifts this vehicle can operate for a full day while two of the crew sleeps on the bunk.

Finally, it needs an operating cost. The flying saucers and other visitor vehicles are powered off crystals, so I want to enforce a cost to operate. Using the cost of a quarter charged crystal as 5gp you can operate a scout at 10 crystals a day giving a cost of 50gp. I think Terran vehicles will have a lower cost, maybe half that, so a much reduced cost of 20% seems appropriate (higher tech will still be much better). I wanted to use a fantastic source, not a mundane fuel. Like gunpowder not being officially called gunpowder in my setting. In the end I came up with Pure Air, sourced from the elemental planes and distilled in the laboratories of alchemists.

Edit: for reinforced vehicles I assume 6HP per HD.

The Tyrant Bird or "Quetzalcoatlus"

As per normal my players have found a flying vehicle and are using it to explore the worldship. This time is a small flying saucer “scout”, last time it was the gyrocopter (my second group are about to find a Visitor Trader and have expressed an interest in finding other worlds, more on that later). As such I need to work on both vehicle combat rules and encounters appropriate to exploring using a vehicle that flies.

So while I work on this I am identifying monsters that can damage vehicles to build the table as well as making a few new monsters. The first is the Quetzalcoatlus. I think this would be called a “Tyrant Bird” by the common folk of the worldship and I have detailed it below:

Dinosaur, Quetzalcoatlus AKA Tyrant Bird (Gigantic animal)

% In Lair: Dungeon Enc: Wilderness Enc: Treasure Type / XP:	None None Flight (1d4) None / 700
Hit Dice: Armor Class: Save: Special Def.:	9 4 F5 None
Movement: Attacks: Morale: Special Off.:	120’(40’) ground; 240' (80') flying Bite (3+, 2d12 [3 VHP, 2 THP]) +1 None

This gigantic pterosaur is the largest known flying animal to have ever lived. These gigantic winged reptiles had wingspans of up to 40 feet. At this size they could be compared to the size of modern aircraft and would have been a tyrant of the skies. To the inhabitants of the worldship this monster would be found in the arboretum jungles and the wider mainlines of their world, they are commonly referred to as the Tyrant Bird. They weigh around 440 pounds but can only carry around 10 stone due to their light bone structure. They would attack animals and large creatures for food and their territorial nature would lead them to attack other airborne creatures or even vehicles such as flying saucers.

Based on original image by Joschua Knüppe

Build notes:

Starting with the Pterosaurian BME 1.35–1.48 rates in L&E I calculated out the 9 HD to achieve the upper mass estimates of the base creature found online (there is a wide range of estimates out there). Coincidently this is another 4HD increase from the Pterandon at 5HD which is itself a 4HD increase on the Pterodactyl. The gigantic size is based off literal dimensions here not mass, similar to other pterosaur in the base book these are lighter mass creatures. In a way I was looking for a gigantic creature so it can damage structures and vehicles. The AC is increased by 1 for no benefit and the damage is above the recommended table but below the upper limit to ensure it can damage vehicles. I increased its moral by 1 given its size and to step each of the pterosaurs by one for each monster size.

The big question was - should it have dive attack? The actual flight and feeding habits of this creature are controversial given difficulty in estimating its mass. As a dominant beak attack I can’t imagine it doing a grab attack similar to a Hawk or Roc using Talons. As such I will just restrict it to standard beak attacks. It can still dive and attack with its beak, it just lacks the bonus damage. That said I have given it an already strong bite attack.

Firearms in the worldship

So, the worldship is a weird setting, it’s a sword and planet setting, a sci-fi game dressed up as a fantasy game. Overall though I seek to maintain relevance to fantasy weapons in amongst more modern and alien weapons.

As most visitor encounters result in several weapons remaining behind I don't treat these weapons as magic item (in most cases). If I did treat them as magic weapons they would be swimming in magic items very early on in the game given the prevelence of these encounters in this setting. I role on the scavenging weapons tables in ACKs to determine the weapons condition when found leading to many being damaged. A side effect of this is technically these weapons can be enchanted, though I leave this up to players to do not include enchanted modern weapons in treasure tables.

In play I give some disadvantages to modern weapons. The main is noise, if they are used in a battle I give +1 to the next random encounter role in a dungeon. Also I “alert” neighbouring rooms, I check who is there and decide what they do to respond. This still leaves the silence advantage strongly in the court of bows and crossbows.

Also I apply a misfire rule draw from warhammer fantasy, on a natural unmodified roll of 1 or 1-3 the weapon can jam or explode. An explosion destroys the weapon and applies the shots damage role to the character firing the weapon. A jam causes the weapon to lock up and it requires a full turn to clean and repair the weapon outside combat.

They have many advantages, under my initiative rules an aimed shot gains a bonus to reducing the targets armor class. If you're not using those rules a simple -2 to the target's AC suffices. Many have access to the rapid fire rules from plasma rifles in Barbarian Conquerors of Kanahu. The final main advantage is simply range, though in cramped corridors and buildings this is often of little use.

Their are three dominant technology levels on the worldship Gaumont, Terran and Visitor.

Gaumont technology

Gaumont is a renaissance era technology level, in the main they use sword and crossbow. But they have access to automatons that are custom build by craftsman that differentiate them for a standard fantasy empire. Firearms are built by these craftsmen, they use meteor powder as the propellant for their weapons, made of arcane powders and dusts concocted by alchemists that is highly explosive. This is bound with wax and paper into a shot cartridge with the bullet that is inserted down the barrel as a single object.

Their designs take strong influence from terran weapons and include rifling, but they still use breach loaded for its sturdy nature and perceived accuracy. While aware of clip based weapons they do not use them more out of cultural preference. With many fights quickly becoming close quarter melees they use these weapons more as an opening salvo before closing. They use a wheellock mechanism drawing on complex clockwork designs that has been perfected over centuries.

Gaumont firearms jam on a natural roll of 2-3 and must be cleared outside combat. On a natural 1 they explode, doing 1d8 damage to user. Cleaves can only occur if a character has multiple pistols loaded and available and has the fighting style proficiency to access the quickdraw feature of that proficiency.

Terran technology

Terran technology reflects technology of the modern world, slightly into the current future. They use chemical propellants, an artificial variant of meteor powder from the Gaumont empire that is more efficient but has similar effect. They use rifling and are breach loaded with ammunition clips. They jam on a natural roll of one and may cleave so long as ammo is in the clip.

The terran weapons and ammunition are deliberately expensive, representing rarity.

Visitor technology

Visitor weapons are Plasma based weapons in the main. They are presented in BCK and follow all rules within. As a house rule they have access to the armor penetration of other modern weapons in my setting and also benefit from cleaves limited to their clip.

Modern Weapon Summary Table

	Cost	Ammo/loading	Ammo cost	Damage	Range Inc.	Notes
Gaumont
Clockwork pistol	100	1/ Cartridge	1gp/shot	1d8	30'	Misfire (1 explode, 2-3 jam)
Clockwork rifle	300	1/ Cartridge	1gp/shot	1d8	70'	Misfire (1 explode, 2-3 jam)
Terran
Auto pistol	250	10/ Clip	5gp/shot	1d8	60'	Misfire (1 jam)
Submachine gun	500	20/ Clip	5gp/shot	1d8	60'	Rapid fire, Misfire (1 jam)
Auto rifle	600	30/ Clip	5gp/shot	1d10	140'	Rapid fire, Misfire (1 jam)
Visitor
Pistol	300	As crystal	1-5gp/shot	2d4	210'	None
Rifle	900	As crystal	3-30gp/shot	2d6	360'	Rapid fire

Structural Automatons

In building larger vehicles I have been struggling with the nature of hit points. The largest automatons can still be damages by a sword. Yet when I read the rules for Galleon SHP are used and these can only be damaged by specific sources. Also, Visitor vehicles in BCK follow an advanced form of SHP that makes them significantly more resilient than their hit dice implies, could such rules be applied to an Automaton?

Automatons cannot take immunities to weapons by their nature, they are not magical. But there is a logic to larger automatons potential being immune to normal sized weapons by being a large structure in nature. 

But this “bonus” should also come with a cost, Galleons have restrictions on repairs and movement. A vehicle of this nature would not be a standard automaton in nature. Also to consider, the vehicle rules used on flying saucers and balancing the differences between technological vehicles and automaton vehicles. 

What is SHP?

SHP is mentioned in the sea combat rules in the ACKS core rules and in domains at war. Here I am considering it more in terms of a galley rather than a fort. Under the standard rules a galley can be damaged by artillery (in full) in addition to Gigantic or larger creatures and magic at a rate of 1 damage per 5 hit points of normal damage. This sounds very similar to the visitor vehicle structure rules I explored in the Visitor Trader post. But repairing a galley in the field is limited to repairing 1 SHP per turn with 5 people and can only repair half the damage.

Repairing technological vehicles is not as difficult as repairing a galley. But then advanced material repair options would be available with Alien Parts that make this less concept breaking.

Damage to a galleon with SHP reduces its movement rate proportionately. As such any vehicle using SHP should have its speed reduced at some point, though calculating rates as damage is taken can be a pain in normal play so maybe a threshold would be easier.

Damage from magic weapons is tricky. Structures receive damage from specific sources, and personal scale weapons are not listed. But technology weapons are not considered either. As such I would say the rules I apply to technological vehicles would apply to a mundane structure, that being 1 damage per 5 for a personal scale technological weapon. A squad of visitors blasting at a stone wall with plasma rifles would certainly make a dint. But then in play fighting a flying saucer the question came up “would a magic arrow damage a flying saucer” they are magic but also a personal weapon. I ruled that magic weapons can do 1 damage per 10 to go a little way in between none and zero. This way mundane characters without technological weapons can do something against alien tech, but it’s still very little. I would only apply this rule to vehicles with SHP.

Overall, these rules should not apply to personal scale automatons, only the largest vehicles would have it available. But how large? Using my rule of 5 from the discussion on large sized automatons I would say the limit should be that required to get the maximum weight of an automaton in the gigantic category from L&E +1HD. That is 800 stone at 9HD lifted to 10HD giving 1,000 stone (7 Tons) or 10 HD for a normal automaton.

The Reinforced Structure ability (granting VHP)

As this is not quite the same as the SHP rules from domains at war and applies to automatons, I will refer to it as Vehicle Hit Points or VHP. Applying the rules for VHP to vehicles should be viewed as an optional rule as follows.

At its most basic this is a positive ability costing a full special (*) called reinforce structure. To take this ability the automaton must weigh over 1,000 stone or 7 tons. This grants the damage immunities as follows:

The reinforced structure of this automaton/vehicle is difficult to damage. Primitive personal weapons deal no damage as does any natural attack from creatures of huge size or smaller, though enchanted weapons deal 1/10th damage. Advanced technological weapons, natural attacks from gigantic creatures or larger and magic deal only 1/5th damage. All artillery or technological vehicle mounted weapons and spells that do direct SHP damage do full damage.

A vehicle with reinforced structure that takes up to half its hit points in damage is restricted in its movement and has its move rate reduced by half.

Automatons with reinforced structure can be repaired in the field only up to half their maximum hit points. This requires the assistance of 4 people in addition to the mechanist to perform but otherwise follows the same rules as repairing standard automatons. Full repairs can be performed in a workshop to the value of the automaton following the normal rules.

VHP vs THP

The following table summarises these resistances for SHP types into two categories for vehicle to represent two different tech levels. VHP is used to signify SHP used on a vehicle/automaton hit points. THP is for technological vehicle hit points used in Vistor vehciles.

Damage source	VHP	THP
Environmental	Full	None
Personal weapons - low tech	None	None
Personal weapons - enchanted	1/10	1/10
Personal weapons - tecnological	1/5	1/5
Artillary - Wood	Full	None
Artillary - Stone	Full	1/10
Artillary - Technological	Full	Full
Creature - Huge or smaller	None	None
Creature - Gigantic	1/5	1/10
Creature - Colossal	1/5	1/5
Magic - Spells	1/5	1/5
Magic - Spells doing SHP	Full	Full

Applying this to current automatons

This ability is easy to add to a current automaton build that weights over 1,000 stone as you are just adding a major ability. Given this is an optional rule consider the nature of the vehicle, this would logically apply to a tank, but should it apply to a wooden frame aircraft? Either way the current design just adds the following to hack this ability onto it:

• +5000 cost
• +5 days to build
• +1 difficulty to build