OSR: Class: Cannoneer (and Cannon Rules)

My generic fantasy OSR setting is based on ~14th century France, England, and Germany. Gunpowder and cannons exist, but they have yet to make any significant impact on the conduct of wars, the design of fortifications, and the conduct of armies. Cannons are rare and dangerous items.

The cannons I'll be discussing are more advanced than the pot-de-fer...

But far less advanced than the cannons you are used to seeing in movies.

The cannons we're discussing are like this:

They are small. Iron or hardwood (!) barrels, muzzle-loaded, with a ~2" bore, firing a 2lb stone ball the size of an apple. A strong person could pick one up and fire from the hip but the recoil would almost certainly knock them flat and break a few bones. They aren't terribly noisy - the gunpowder of the era explodes with a slow "fwoosh" rather than a sharp modern "crack". The impact isn't utterly body-shattering. Anything it hits will be broken or torn apart, sure, but you can still find all the pieces in more or less their original shape.  Keep these facts in mind when you're reviewing the stats below. It's the primitive ancestor of guns like this.

I'm not going to spend pages detailing the types of barrels, chambers, and shots. I don't care what type of polearm you use (they're all heavy weapons with reach), and I definitely don't care if the cannon I'm describing is perfectly accurate. It's within the margin of historical error. Times and weights are based on estimates, shoddy math, and lots of American civil war historical reenactment videos.

Cannon (2lb)

Range: Roll required to hit a single target
<10': Attack + 8
10' - 200': Attack
200' - 400': Attack - 8
400' - 600': Only on a critical success

Targets of the cannon do not gain an AC/Defense bonus from armour. Large targets may provide a bonus to hit at close range. On a miss, something is still struck by the cannonball. If the cannon is fired at a group of closely packed targets, an Attack roll may not be required (if you're shooting at a horde of goblins, you're going to hit a goblin).

Damage: 4d6. Target must also Save or be stunned. If a 1 or 2 HD creature is killed, creatures immediately behind them in a straight line take any excess damage. 

Cannons also make a lot of noise. Roll for wandering monsters (or any other noise/alertness-based effect) every time the cannon is fired. If the cannon is fired in a narrow space (<20'x20'), everyone in the space must Save or be partially deafened for 1d6 hours. Smoke fills a 10' square.

Reloading
An untrained team of three loading or firing a cannon must roll on the Misfire table. An untrained team can load a cannon in 10 rounds (Int checks may be required). If they rush, roll on the Misfire table with a +4 bonus.

A trained team of three can reload a cannon in 5 rounds. If they rush, it can be reloaded in 4 rounds, but a roll on the Misfire table is required.

Misfire Table
Roll if you rush or if the loading process was interrupted, chaotic, or unsafe.

1d10	Misfire Effect
1-3	No Effect. The cannon fires normally after a 1/10th of a second pause (just long enough to worry).
4-5	Match Extinguished. The cannon does not fire this round. The cannon can be fired normally next round.
6-7	Fizzle. The cannon fires in 1d4 rounds (roll secretly).
8	Bad Load. The powder half-detonates. The ball flies 30',dealing 2d6 damage. Takes 2 extra rounds to reload.
9	Dud. The powder does not ignite. Takes 4 extra rounds to reload.
10	Split. The ball shatters as it leaves the barrel. 30' cone, 1d6 damage. Crew must Save or be hit by shrapnel.
11-12	Spiked. The cannon partially detonates. 20' radius, 1d6 damage, Save for half. Cannon cannot be fired until repaired.
13+	Shattered. The cannon detonates spectacularly. 30' radius, 3d6 damage, Save for half. Cannon is gone.

Inventory Management
In my game, Inventory Slots = Strength.

Item	Weight	Inventory Slots	Cost (City)	Cost (Rural)
Cannon	200lbs	14	-	-
Cart	60lbs	6	3gp	3gp
Shot	2lbs	1/3rd	1sp	2sp
Gunpowder (per shot)	1lb	1/3rd	4sp	-
Shot+Gunpowder Packet	3lbs	1	5sp	-
Swab + Rod	5lbs	2	2sp	2sp

Ordinarily you'd use a team of 2 mules: one for the cannon and one for the cart and shot. Dungeons are notorious for eating mules.

Since you need a team of 3 to fire the cannon anyway, 2 members of the team carry the cannon and cart (20 inventory slots split over 2 people = 10 each). The third team member carries the Swab+Rod and the powder and shot. Carrying pre-made charges takes up slightly more space but makes loading and firing the cannon much more convenient. One member of the team should probably carry rope and wooden pulleys for difficult climbs.

When fully assembled, the cannon and cart resemble a primitive two-wheeled barrow. It can be pulled or pushed by one person at 1/2 normal pace, or by two people at normal pace. The cart can be pushed up standard stairs without significant difficulty. Rough terrain, gaps larger than 8", or steep slopes cannot be traversed by the cart. It must be disassembled and rebuilt on the other side. It takes 4 rounds for a trained team of 3 to disassemble or reassemble the cart. Untrained teams could take up to 10 minutes.

Cannons are so rare they cannot be purchased. Instead, anyone with the Cannoneer skill, 300gp in raw materials (iron, clay, wax, etc.), and access to a forge can make a cannon in 2 weeks. Limited tools, distractions, or modifications may add 1d4 weeks.

Gunpowder can only be made by someone with the Alchemist or Cannoneer skills. The costs listed above are for the raw ingredients. 

Dwarf with Cannon, LittleDruid

Cannoneer

Starting Equipment: 2lb Cannon, Cart, Swab+Rod, 3 Shot+Gunpowder Packets
Starting Skill: See below. In addition, you gain the Cannoneer skill.

A: Trained Crew, Bombard's Eye
B: Bomme-Maker
C: Furious Engine
D: Master Cannoneer

You gain a +1 to Save vs Fear for each Cannoneer template you possess. Additionally, you are partially deaf. You can hear normal speech but not whispers or subtle sounds.

Trained Crew
You gain 2 hirelings trained in the use and maintenance of a cannon. All stats are 10 except for Strength, which is 12. You manage their inventory. They are reasonably competent, willing to follow you into combat, and difficult to replace. You need to pay them 2gp per month each. Roll on the Horrible Peasant NPC generator for details.

Bombard's Eye
If you fire a cannon at a stationary or nearly stationary target and miss, your next Attack roll against the target gains a +4 bonus. This bonus does not stack with multiple attempts. If you would hit only on a critical success (400'-600'), you still only hit on a critical success.

Bomme-Maker
You can rapidly craft a crude but controlled gunpowder bomb without any risk or skill check. Crafting requires 1 charge of gunpowder and some added shrapnel. It takes 2 rounds. The bomme deals 2d6 damage in a 20' radius. The fuse can be set to any time, from instant (explodes in your hand) to 10 minutes. It can be thrown (as a dagger). It can also be used to open doors or crack stone.

Furious Engine
If you lead a trained team of 3, you can reload a cannon in 4 rounds rather than 5. If you rush, you can reload the cannon in 3 rounds, but you must roll on the Misfire table. Additionally, anyone who surprises you while you are working on something (an assassin, an unexpected visitor, etc.) must Save vs Fear or make a Morale check when you yell at them.

Master Cannoneer
You can reroll any result on the Misfire table. Additionally, you can select small or unlikely targets with your cannon (someone's hat, a doorknob at 200', an apple on a child's head, someone hiding just around a corner, etc.).

Mechanical Notes on the Cannoneer

The ability to repeatedly fire a maximum power fireball might seem overpowered. The downsides to using a cannon should more than balance it out. Cannons are excellent solutions to many problems... but they create several more. This isn't a core class like Fighter or Thief or Wizard. Despite all the rules above, it's less complicated than a Wizard or another caster class. The main thing a Cannoneer needs to manage is inventory slots. They can't easily loot or wear armour or even carry extra items.

I didn't put in rules for what happens if someone carrying gunpowder is set on fire. I don't think I need to.

Statue of the remarkable Angelina Eberly firing a cannon to start the bizarre Texas Archive War.

Where did you learn this deadly art?

Cannons are rare. For most people, the first cannon they ever see will be yours. There are no gender restrictions on this class. People may scoff but never to your face. You belong to the Third Estate, but your profession brings you a certain degree of respect.

Skill: 1. Soldier, 2: Foreign Parts, 3: Unusual

Soldier
1. You served well and fought bravely but your service was not rewarded. You have gone to seek your fortune elsewhere. You start with no money, but your amazing tales will earn you friends.
2. You served on the losing side of a recent War. You speak an additional language.
3. A former pupil stole your secrets and usurped you. Start with a dagger.
4. You were wounded in an explosion that also killed your employer. Start with an Interesting Scar and 2sp.
5. You participated in a long siege. Start with 3 rations.
6. Your experience in the War changed you. If you fail a Save vs Fear, you will freeze rather than run. If you pass, your hirelings automatically pass.

Foreign Parts
1. You have traveled for most of your life. You never gain fatigue from riding or walking.
2. Start with an appearance and native language so unusual that, to most people, your profession is the second most shocking thing about you. Make up 1d6 ludicrous lies.
3. Your clothing is unusual. Start with robes worth 5sp. You can conceal one apple-sized item inside them.
4. In your country, cannons are as common as rabbits, and wars are prosecuted without mercy. Start with a pair of leather gloves.
5. Your crimes in Foreign Parts were numerous and disreputable. You can evaluate the approximate worth of items (as a Thief).
6. You know the secrets of mathematics. Start with the Mathematics skill and a book.

Unusual
1. You made a pact with a fire elemental. Start with a small lantern (illuminates 10', lasts 24hrs/flask) and 3 flasks of oil. Gain a +4 to Save vs Fire. If the flame in the lantern ever goes out, you permanently lose half your HP.
2. You woke up next to your cannon with no memory of how you got there. Your skills are fresh; your memory is blank before last week. Roll on the Table of Professions and gain the skill listed. You do not consciously know you have this skill.
3. You believe gunpowder can cure many ailments. You can Save to remove a curse, disease, or enchantment if you eat a spoonful of gunpowder. You can only make 1 attempt per condition. This effect only works on you. You don't know this.
4. Your back is strong. You can spend 2 HP to gain +1 inventory slot for 1 hour. You can repeat this process as many times as you would like.
5. You are missing three fingers and one eye. Start with +2 HP. You don't sleep well.
6. Chose a visible profession (Wizards, Priests, Cheesemongers, etc.) A member of that profession wronged you in the past. In combat, you gain a +4 bonus to Attack the first time you fire your cannon at a member of this profession, but you must Save or chose them as your first target.

Further Reading:
Ancient Cannon in Europe (main source)
The Pirate King - Early Smoothbore Cannon