Light Cannon (3.5e Equipment)
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 Light cannon
|Small||2400 gp||400 lbs.||70||1070 ft.|
|Medium||2400 gp||800 lbs.||139||2140 ft.|
|Large||4800 gp||1600 lbs.||277||1605 ft.|
|Huge||9600 gp||3200 lbs.||554||1070 ft.|
A light cannon is a type of relatively light cannon. A light cannon has two large wheels and a third stabilizing leg. The listed sizes are for the operating creature's size; the gun itself is one size category larger than the creatures operating it. Cannons with an operator size smaller than Small or larger than Huge are ineffective.
 Operating a light cannon
To either reload or fire a light cannon, all involved must have the corresponding Martial Weapon Proficiency feat.
To fire a light cannon requires a crew of 1-8 people, one of whom is the primary operator, responsible for aiming the cannon and directing the crew.
To fire a light cannon, it must first be reloaded. Reloading a light cannon with a crew of 7 or more requires 10 rounds; with a crew of 4-6 11+1d4 rounds; with a crew of 2-3, 12+2d6 rounds, and with 1 person, 14+2d5 rounds and a DC 15 Strength check.
(Roll a d5 in the same manner as you would a d3, but with a d10 at the base die. Map each number on a hemisphere of the d10 to one of the possible results for both hemispheres.)
Firing a loaded light cannon requires only a standard action on the part of one of the crew members and a source of fire to light the fuse. It fires at the start of that character's next action. A long fuse may be used for safety, in that case the gun waits 1d6 rounds before firing as the fuse burns down.
The primary operator chooses a target square, and makes an attack roll against AC 8 + 2 for every 300 feet of distance, on that square one round before the cannon is fired. Success means that the cannon will fire to the square it was aimed at. Failure means that the cannon will aim at a different target square. Determine the new target square as follows, unless a natural 1 was rolled on the attack roll.
Roll d8 to determine which direction the deviation is in. The deviation is by 1d20×5 feet in that direction. Repeat this twice more,, each time starting from the square determined the previous time. A deviation so great that the shot will not land within a standard cone starting at the cannon indicates that the cannon did not fire and may have its fuse replaced (a standard action) and be fired during the next round without needing to reload.
Rolling a natural 1 on the attack roll indicates that the gun has misfired, and the one responsible for aiming it must pass a DC 10 Intelligence check or the gun will explode, dealing 12d6 slashing and piercing damage to all creatures within a 20-foot radius due to shrapnel, with a DC 20 Reflex save being possible for half-damage. Passing the check means that the gun simply did not fire and may be fired again as soon as its fuse can be replaced.
When the gun fires, creatures within 15 feet must make a DC 12 Reflex save or be deafened for 2d6 rounds.
After the gun is fired, a cloud with the same size category as the cannon (1 size category higher than its operators) appears in front of the cannon. All creatures within this cloud, including the operators, must make a DC 10 Fortitude save at the start of their rounds or be able to only take a standard or move action in that round due to coughing and choking. If more than 50% of the crew, or the primary operator, are so incapacitated while trying to reload, the round is wasted for purposes of reloading. (There is a 50% chance that any given crew member is in front of the cannon, except for the primary operator when the crew is 7 or more.) The cloud moves 5 feet per round for every 5 mph of wind in the direction of the wind. It dissipates in 2d6 rounds in light wind, 1d6 rounds in moderate wind, and 1 round in strong wind, and immediately in severe or stronger wind.
 Types of shot
A light cannon may fire one of several types of shot. Costs include the cost of the required black powder.
Ball: A single iron ball. In a line of length equal to half the range, starting at the targeted square, all creatures and objects take 4d6 Bludgeoning damage. A Small cannon deals 3d6, a Large cannon deals 6d6, and a Huge cannon deals 8d6. A DC 17 Reflex save is possible for half damage. Reduce the line's length by 5 feet for every 5 points of damage it deals (before applying damage reduction.) If it hits a very solid object (such as a cliff or the Tarrasque), it deals triple damage and immediately ends.
If a creature is taking cover behind a tower shield, the damage is dealt to the tower shield, then to the creature if the tower shield is destroyed.
Cost: 20 GP.
Explosive shell: An explosive shell is a ray attack. On the square where it hits, it deals 6d8 (4d8 S, 8d8 L, 12d8 H) Fire, Piercing and Bludgeoning damage with an explosion, without a save. Creatures within 20 feet take 4d6 (3d6 S, 6d6 L, 8d6 H) Fire, Piercing, and Bludgeoning damage with a DC 17 Reflex save possible for half damage.
Cost: 100 GP.
Chain shot: For this projectile, the cannon's range is halved and the attack roll takes a -3 penalty. In a line from the cannon to the maximum range and with a width equal to the operating creature's size's space, passing through the target square, this projectile deals 4d8 (3d8 S, 6d8 L, 8d8 H) Slashing and Bludgeoning damage. On squares within 5 feet of this line (but not including those of the cannon itself) the projectile deals 2d6 (S 1d10, L 3d6, H 4d6) Bludgeoning damage.
Cost: 40 GP.
Canister shot: For this projectile, the attack roll means nothing unless it is a natural 1, which is as usual a misfire. The shot hits targets in a cone of length equal to 1/4 of the cannon's range. The shot deals 3d6 Piercing and Bludgeoning damage to all creatures within the cone. Add 1d6 for each size category larger than Medium that either the cannon's intended operators or its target are, and subtract 1d6 for each size category smaller than Medium that either the cannon's intended operators or its target are. A Reflex save (DC 18) is possible for half damage.
Cost: 30 GP.