Note: all of this is untested, please write to me if you find something stupid so I can fix it.

There are many ways to travel through the boundless expanses of the world. Guzzolene chugging metal steeds driving across the grasslands, triremes filled with drug-addled slaves that swim both on the perilous oceans and up or down the rivers. There is one method suprerior to all of them - The Mighty Airship, for no other method can go anywhere, right up to tops of the tallest mountains. In order to have a ship fly you need three things:

1. Hydrogen.

This wonderful gas can be obtained by powerful wizards or great factories by filling water with lightning. It is used both as what keeps the ships up and as the gas that is burned to push it forward. Hydrogen is usually measured in "reverse weight", or how much it can hold up in the sky. -100 kg of hydrogen usually costs between 2 to 10 GP, depending on the output of the nearby factory and the local demand.

2. A Light Ship.

Most airships are made out of light wood and leather, all covered in fire-proof enchanted leather. The part that holds the hydrogen is always larger than the ship itself. They use both sails and hydrogen-powered propellers to sail across the skies, with lighter ships relying more on the hydrogen they can burn and the heaavier ones relying on their larger sails. Ships are divided into:

• Light Ships (Weight: 100 000 kg, require 20 crew men, Hull length: ~20 m, Width: ~7 m, Depth ~4 m) Can store -125 000 kg of hydrogen in itself. Sails at the speed of 1/10th of the wind's speed. Can burn -100 kg of hydrogen per hour in order to gain 30 km/h. 200 HP. Costs ~4 000 GP

• Medium Ships (weight: 300 000 kg, require 50 crew men, Hull length: ~50 m, Width: ~10 m, Depth ~7 m) Can store -400 000 kg of hydrogen in itself. Sails at the speed of 1/5th of the wind's speed. Can burn -200 kg of hydrogen per hour in order to gain 20 km/h. 600 HP. Costs ~8 000 GP

• Heavy Ships (weight: 600 000 kg, require 80 crew men, Hull length: ~80 m, Width: ~15 m, Depth ~10 m) Can store -800 000 kg of hydrogen in itself. Sails at the speed of 1/2th of the wind's speed. Can burn -500 kg of hydrogen per hour in order to gain 10 km/h. 1 200 HP. Costs ~15 000 GP

When you've seen the values of HP you might have thought "what could bring these beasts down?" Hold your horses. Most airships avoid fighting, as there too many fights in which everyone loses. Here are some examples of terrible weapons that are used in airship combat:

• Cannon (0.7 km range, 6d10+10 damage, -10 penalty to aim at anything smaller than a ship, 10 000 kg weight, costs ~2 000 GP)
• Harpoon Cannon (1 km range, 5d6+12 damage, -10 penalty to aim at anything smaller than a ship, 5 000 kg weight, costs ~1 000 GP)
• Fire Belcher (0.1 km range, causes 3d12+12 strength fire and kills twice as many crew members, -10 penalty to aim at anything smaller than a ship, 10 000 kg weight, costs ~1 000 GP)
• Burning Harpoon Cannon (1 km range, 3d6+12 damage and 2d12+6 strength of fire, -10 penalty to aim at anything smaller than a ship, 5 000 kg weight, costs ~4 000 GP)
• Maniacal Mirror Array (3 km range, causes a d12+3 strength fire, 2 000 kg weight, costs ~1 000 GP)
• Barbed Ball Cannon (0.5 km range, 5d10+20 damage, kills twice as many crewmembers, -10 penalty to aim at anything smaller than a ship, 10 000 kg weight, costs ~3 000 GP)

If a ship lost 1/4 HP it begins losing hydrogen: -500 kg per turn until it is patched up (an hour of work for a full crew) 1/2 HP: The loss goes up to -1000 kg per turn. 3/4 HP: The ship is falling apart. It can not be fixed without going to the ground, losing -2000 kg per turn. The only thing left is trying to safely land it. All HP Lost: The ship falls to the ground. You are absolutely fucked.
Strength of fire causes damage equal to itself during each turn of an air combat. Each crewmate assigned to extinguishing it reduces the strength by 1 for each turn. If a ship has lost more than 1/4 HP then roll a d4 each turn. On a 1 it explodes, causing its HP to fall down to 0.

3. Crew

The blood of a ship. They are those who make a ship fly, just as important as hydrogen. During a fight, each time a ship is hit by an attack d4-1 crewmembers die. Each weapon that is manned by 5 people can fire once per turn. If a ship loses the required crew it also loses maneuverability(the fewer crewmember, the more it falls). They can also spend a turn patching the ship up, restoring 1 HP per each crewman working.