Siege Weapons
    Weapons in space have followed along the lines of their ground counterparts, and are the descendants of siege machinery and large naval weapons. In addition to the wide variety of personal weapons and magical abilities, there is a collection of catapults, ballistas, trebuchets, and scorpions available to the buyer, as well as a variety of rams. Bombards and other 'cannon' are used, but are not common — their effectiveness is doubtful, their powers change from sphere to sphere, and the explosive nature of the phlogiston makes carrying them dangerous at best.
    All of the standard ships are capable of carrying a base number of large weapons. The weapons themselves are not included in the cost of the ships — these are merely places where the buyer can install weapons without as given in the deck plans. Each weapon takes up 'space' on deck thus it is possible to have a deck is littered with seige weapons but doing so will cause crew to have to climb over equipment to just to move around deck ... this can only lead to mishaps and possibly death.
    Ships typically have only a single ram, if they have any at all. If the ram is listed with the ship's hull description, then it is an integral part of the ship. Otherwise it must be bought and installed.
    Weapons are listed in terms of hit points of damage they inflict (this applies to ship and personal equally in 3E), the number full rounds need load or reload the siege weapon. A minimum number of crew is needed to fire at optimal rate of fire. If it is required for a single person to load a siege weapon, it will take a long time (figure this by mulipling the crew size by the number of rounds to reload ... so that a single person could reload a heavy cannon in 20 rounds).
    Siege weapons are range weapon with only bare minimum amount of dexterity due to its crew having to manually place them into position in order to hit. Nor do ships weapons take any bonus/penalty to size as the number of crew members and their training compensates for this. Thus all siege weapons take a –5 to hit in combat. Only feats or very special training (see Siege Specialist) can allow for siege weapons to have a better chance to hit.
    Each siege weapon on a natural to hit roll of 20 will possibly cause Collateral Damage. The exception being cannons and bombards which have a chance to cause collateral damage on a natural 19 or 20. A second roll to hit is required to determine if indeed a ship has taken collateral damage (this is much like causing critical damage). See combat section more on what results when a collateral damage strike is confirmed.

Table 7–3: Siege Weapons
Weapon Damage Critical Increment Reload Crew Type Cost
Ballista, Light 2d6 19-20/x2 80 feet 3 2 Piercing 400 gp
Ballista, Medium 3d6 19-20/x2 120 feet 3 3 Piercing 600 gp
Ballista, Heavy 4d6 19-20/x2 160 feet 4 3 Piercing 800 gp
Ballista, Dual Light 2d6 19-20/x2 80 feet 3 4 Piercing 800 gp
Ballista, Dual Med 3d6 19-20/x2 120 feet 4 5 Piercing 1,200 gp
Ballista, Dual Heavy 4d6 19-20/x2 160 feet 4 6 Piercing 1,600 gp
Swivel Cannon 2d10 x2 160 feet 3 2 Bludgeoning 1,000 gp
Light Cannon 4d10 x2 200 feet 3 4 Bludgeoning 2,000 gp
Heavy Cannon 6d10 x2 200 feet 4 5 Bludgeoning 5,000 gp
Bombard, Great 10d10 x2 320 feet 6 5 Bludgeoning 30,000 gp
Catapult, Light 2d10 x2 120 feet 3 2 Bludgeoning 500 gp
Catapult, Medium 3d10 x2 160 feet 3 3 Bludgeoning 700 gp
Catapult, Heavy 4d10 x2 200 feet 4 3 Bludgeoning 1,000 gp
Gnomish, Sweepers 2d6 x2 160 feet 3 4 Slashing 800 gp
Alchemist Fire Projector 3d6 x2 10 feet Special 1 Fire 1,000 gp
Jettison, light 2d4 x2 120 feet 3 2 Bludgeoning 400 gp
Jettison, medium 3d4 x2 160 feet 3 3 Bludgeoning 600 gp
Jettison, heavy 4d4 x2 200 feet 4 3 Bludgeoning 800 gp

    Ballistas: Ballistas include all devices, which throw bolts, javelins, and spears with greater force than possible by human (or inhuman) strength. Most are built along the lines of the crossbow, and are mounted on pivots on the ship's deck to fire at any targets.
    Light Ballista: The light ballista is medium in size and has the following characteristics: Hardness 5; 20 hit points; AC 10 (Dex —), Space 5 feet.
    Medium Ballista: The medium ballista is large in size and has the following characteristics: Hardness 5; 30 hit points; AC 9 (Dex —, –1 size), Space 10 feet.
    Heavy Ballista: The large ballista is large in size and has the following characteristics: Hardness 5; 30 hit points; AC 9 (Dex —, –1 size), Space 10 feet.
    Ballistae, Dual-Mounted: Dual-mounted ballistae have room for two ballista bolts along the weapon's main beam, allowing for multi-bolt firing. The firing cord is firmed and specially costed across the pull's apex to allow for dual firing without the bolts striking each other as they soar from the weapon. The duel-mounted ballista fires the two bolts together, approximately six to eight inches apart. The damage listed is for each individual bolt
    Note: If the dual-mounted ballistae is used to fire only one bolt, the weapon takes an —2 circumstance penalty to hit.
    Dual-mounted ballistae use the same hardness, hit points, AC and Space as its single bolt predecessors.
    Cannons:These items (also refered to as bombards) are very rare in the Known Spheres, for a variety of reasons. They ten to be unreliable, both from the standpoint of being physically untrustworthy and more importantly, because the chemical or magical reactions they depend on sometimes vary from one world to another. Gunpowder may work perfectly inside one shell, only to be inert in another, and is a magical jewelry polish in a third. These differences are often written off as the whims of the gods themselves; to keep mortals in their place, but the results is that cannons are rare. The other reason that cannons is rare is that fire travels poorly through the phlogiston, and many a ship has exploded as the result of a poorly protected smoke powder magazine. If the DM chooses to allow cannons to operate in a particular sphere, any collateral hit has a 10% chance of igniting the smoke powder magazine, inflicting 2d10 points of damage and 5 feet radius explosion per 10 charges in the magazine. A magazine typically can hold up to 100 charges and if a magazine has 100 charges it will explode for 20d10 points of damage in a 50-foot radius (naturally this damage and radius is tripled in the phlogiston!).
    Cannons are typically resting on a wooden carriage (some cannons like the swivel cannon are fixed in position once mounted, though they can be remounted in 1d4 minutes in a new position). These carriages can be move to a new position on a ship given enough time.
    Cannons use magical smoke powder to function. One shot uses 10 charges of powder. The scarcity of smoke powder (which is a magical substance in fantasy space) makes bombards impractical compared to ballistas and catapults. It should be noted that the Great Bombard takes 20 charges of smoke power to fire its massive iron balls.
    Swivel Cannon: The swivel cannon is small in size and has the following characteristics: Hardness 10; 15 hit points; AC 11 (Dex —, +1 size), Space 5 feet. The iron shot for this cannon weighs 7 pounds.
    Light Cannon: The light cannon (also known as 15 lb. cannon) is large in size and has the following characteristics: Hardness 10; 30 hit points; AC 9 (Dex —, –1 size), Space 10 feet.
    Heavy Cannon: The heavy cannon (also known as 24 lb. cannon) is large in size and has the following characteristics: Hardness 10; 30 hit points; AC 9 (Dex —, –1 size), Space 10 feet.
    Great Bombard: The great bombard is gargantuan in size and has the following characteristics: Hardness 10; 80 hit points; AC 6 (Dex —, –4 size), Space 10 feet by 80 feet. It is so big that it is built into a ship's design. It is often joked that the great bombard shot weighs as much a giff and many sailors have affectionately refer these shots as 'dead giffs' (the weight of each shot is 640 pounds). Because of the weight of the shots, Giff Bireme have a winch to haul these heavy shots to the bombard (and each of the shots have 'handles' so the winch's chain can attach to the shot). It should be noted that *while* the great bombard is not a practical weapon, leave it to the giffs to create such a monster of a weapon.
    Catapults: The general category of catapults is large, stone-throwing devices operated by springs, cranks, or flywheels. Catapults are fixed in position once mounted and can fire only one direction. A catapult firing forward is permitted to fire at any target across its trajectory to a maximum of 10 range increments. All ranges take into account the nature of wildspace and the Flow.
    Catapults can be loaded with stone shot instead of large rocks. Stone shots is most effective as an antipersonnel weapon and will not affect a ship as effectively as the damage drops from d10 to d4 (the ship's hardness will prevent much of this damage), but effects all personal within a 10 foot radius of the spot where it hits.
    Special: Catapults cannot attack a ships that is within 100 feet of the catapult.
    Light Catapult: The light catapult is large in size and has the following characteristics: Hardness 5; 30 hit points; AC 9 (Dex —, –1 size), Space 10 feet.
    Medium Catapult: The medium catapult is huge in size and has the following characteristics: Hardness 5; 50 hit points; AC 8 (Dex —, –2 size), Space 10 feet.
    Heavy Catapult: The heavy catapult is gargantuan in size and has the following characteristics: Hardness 5; 80 hit points; AC 6 (Dex —, –4 size), Space 15 feet.
    Gnomish Sweepers: The saying goes, there is nothing in the universe that a gnome cannot make more dangerous, and when the small creatures turn their attention to weaponry, most intelligent species (except perhaps the Giff) move to another sector of space. Occasionally, the gnomes come up with an invention that works most of the time, which they then release on an unsuspecting galaxy, usually cheapening the quality in order to bring the price down.
    Gnomish sweepers are an example of such a device. Still experimental, they are nothing more than a pair of light ballistas with a common mount so that they can be fired in the same direction at the same time. The two bolts are linked with a heavy chain. The intention of the chain is to be used as an antipersonnel weapon against enemy crews.
    Early versions of the sweepers used chains long and thin enough to capture a couple of small sized opponents, but soon worked out the bugs to the point that they could use them against human opponents. The other problem with the sweepers remains uncorrected — when the chain strikes something heavy, like a mast, weapon turret, or other piece of deck furniture, chain tangles and is useless.
    A gnomish sweeper affects all targets in a 10-foot square. It will continue on into the next 10 foot square away from the ship firing it unless it meets with large, unmovable object, which cause it to drop to the deck. In addition, every target within the 10-foot square is forced to make a Reflex save (DC 20) to remain standing, the same as if a Ship Shaken critical hit had occurred.
    The gnomish sweeper does not inflict hull damage but can be used as a duel light ballista in a crunch, with the same requirements for crew and reload time as a duel light ballista (the weapon does not fire unless both bolts are loaded).
    The gnomish sweeper's use as a weapon can be argued by military sage, but it should be noted that after an initial outpouring that saw most gnomish ships carrying a sweeper, practically no new gnomish ships carry the weapons. Gnomish sweeper has a collateral threat value of 20/1.
    Gnomish Sweeper: The gnomish sweeper is large in size and has the following characteristics: Hardness 5; 50 hit points; AC 8 (Dex —, –2 size), Space 15 feet.
    Alchemist Fire Projectors: This swivel mounted device shoot a thin stream of flaming, explosive liquid. Though it can be devastating in combat, like bombards the alchemist fire projectors are not popular with ships that cross between the spheres because of the flammability of the Flow. In fact, alchemist fire projectors are recipes for disaster in the phlogiston. They are popular, however among crews that do not leave their spheres.
    Alchemist fire projectors are only effective when two ships are close enough to share a common air envelope, as the alchemical substance will be snuffed out if it passes into any hex that does not have an air envelope.
    Projectors affect the target and all others within a 5-foot radius delivering 3d6 hit points of damage. On the following round the targets takes an additional 3d6 hit points of damage. Targets can take a full round action to attempt to extinguish the flames before taking this additional damage. It takes a successful Reflex saving throw (DC 15) to extinguish the flames. Rolling on the ground allows the character a +2 bonus. Leaping into a body of water that has sufficient volume to be fully submerged or magically extinguishing the flames automatically smothers the flames.
    Ships carrying alchemist fire projectors are more vulnerable to collateral hits, and ships attacking them increase the collateral hit threat range by one (i.e. 19–20) to determine whether a collateral hit has occurred. For example, a medium catapult has just scored a to hit roll of 19, normally this is not a collateral hit, but cause the ship it it has an alchemist fire projector, it has scored a collateral hit. Roll a second to hit to confirm that the ship has indeed taken an collateral hit.
    Alchemist fire projectors start fires where they hit, even on stone and treated wood: flammable materials nearby will catch fire and feed the flames. (See fire in the next chapter).
    Alchemist fire projectors have a piping that runs to a pressurized cylinder that contains 10 shots. When the cylinder runs dry, another has to be fitted into place; this requires 2 full round actions to perform by some very strong crew (some ships have multipule cylinders below deck and only requires a crew member to close one valve leading to the empty cylinder and then open valve to a full cylinder). Replacing cylinders is hard work as they are quite heavy. During the rounds that the pressurized cylinders of alchemist fire are not being replaced the alchemist fire projector is able to be fired once once per round.
    Alchemist Fire Projector: The alchemist fire projector is medium in size and has the following characteristics: Hardness 10; 20 hit points; AC 10 (Dex —), Space 5 feet. Below deck is a rack of Alchemist Fire Cylinders with a piping that runs to each one. Only one valve is open at any given time to reduce risk to ship.
    Jettisons: A jettison consists of a series of small catapults loaded with stones, trash, debris, iron spikes, and garbage, and used as an anti-personnel weapon to clear the enemy's decks. Any type of catapult can be converted into a jettison of the same size by loading it with small rocks instead of a single stone. A jettison, however cannot be converted into a catapult.
    Jettisons are mounted in place and cannot be moved. When fired, they hit a spot on the ship and may affect every target within the weapons radius (hitting a particular 5 feet square is AC 9). Those within the area of the jettison attack may take half damage if a Reflex save DC 10 + damage done is made. The spell protection form arrows will protect individuals from damage of a jettison attack. Because of the shear volume of projectiles the feat 'deflect arrow' reduces only one die of damage from the incoming attack against the individual that has the 'deflect arrow' feat. The radius is dependent on the size of the jettison with light jettison have a 5 foot radius, medium having a 10 foot radius, and heavy having 15 foot radius.
    Many spelljammers use catapults as temporary jettisons when they need to. Often jettisons are mounted at the rear of ships to deter pursuers.
    A jettison can be fired at an empty hex. This automatically sets up a field of debris in that hex (see Combat).
    Light Jettison: The light jettison is large in size and has the following characteristics: Hardness 5; 30 hit points; AC 9 (Dex —, –1 size), Space 10 feet.
    Medium Jettison: The medium jettison is huge in size and has the following characteristics: Hardness 5; 50 hit points; AC 8 (Dex —, –2 size), Space 10 feet.
    Heavy Jettison: The heavy jettison is gargantuan in size and has the following characteristics: Hardness 5; 80 hit points; AC 6 (Dex —, –4 size), Space 15 feet.
    Rams: The effects of ramming are covered in combat. They depend on the relative sizes of the ship doing the ramming and its target. There are several different types of rams, however.
    Piercing Ram: A piercing ram is a long, sharp prow used to break open and break apart an enemy ship. An attack with a piercing ram can sometimes result in the two ships being locked together.
    Blunt Ram: This is a flattened ram designed to inflict internal damage by shaking up the smaller ship. It can also break up other ships, but there is no change the ships will become locked together after ramming.
    Grappling Ram: The grappling ram incorporates one or more movable arms which attach themselves to an opponent's ship after ramming, locking the ships together, very useful during boarding situations. A grappling ram can also inflict damage on smaller ships.
    Turrets: A turret is a rotating platform. Weapons mounted on turrets can be turned to face different targets quickly. For example, a heavy catapult mounted on a turret can be swung to attack any ship in a 360-degree range.
    Turrets can also provide shield bonus cover for the crew. Protected turrets are available at double the initial cost, and provide +4 shield bonus to the crew manning that heavy weapon. Small weapons can be moved easily without a turret, but they can benefit from the cover a turret provides. A turret is typically made of metal (hardness 10, 30 hit points) ½ inch thick.
    Alchemist Fire: Alchemist fire is a sticky, adhesive substance. It usually is stored in stone or ceramic jugs, each jug containing enough alchemist fire for one shot. Loaded into an alchemist fire projector and lit, it fires a stream of flame, which can set almost any target ablaze. No one has yet refined it to the point where a hand-held projector is feasible.
    Alchemist fire is always flammable. If a cask is opened and comes in contact with fire, it will explode automatically, causing 3d6 hit points of damage to everyone within a 5-foot radius, and causing additional damage next round as if the alchemist fire landed in that exact same spot. Any other alchemist fire containers exposed to this explosion will also explode with identical results unless their containers withstand the damage. Exploding alchemist fire also causes a fire in the hold.
    The largest gnomish ship ever built — so far as is known — the Dreadnever, was destroyed in this fashion when improperly stored alchemist fire was touched off in the ship's magazine. The captain's last recorded words were “It's awful dark in here”)
    Ballista Bolts: A ballista bolt is a large arrow used in all the standard ballistas. A standard ballista bolt will fit a light, medium, or heavy ballista. The difference in damage is caused by the power of the ballista's mechanism.
    Catapult Stones: Unlike ballista bolts, three types of catapults stones are available, one for each type of catapult: light, medium, and heavy. Only the proper sort of stone is really useful in each type of catapult. A copper-pinching captain can use any type of similarly sized and readily available rock to inflict similar damage, and some combats have involved tossing tables, dead bodies, cows, and other items through space as shot.
    Stone shot and Jettison shot: A bundle of stone shot or jettison shot can fit any catapult or jettison. Usually this type of shot is stored as packages of rocks in thick bags, which burst when fired. Almost any sort of stuff can be substituted in an emergency.
    Bombard Shot: Two types of shot are used in bombards: large, round stones and cast iron “cannonballs.” Using the latter increases the bombard's damage against a ship but not against crewmembers. (Stone shot often breaks up on impact, scattering sharp fragments, while iron is less likely to do so.) Bombards using iron shot have a +2 circumstance modifier to hit.
    Smoke Powder: This wondrous substance is similar, though not identical, to gunpowder. It is extremely scarce and, due to its volatile nature, dangerous to fabricate. Smoke powder will be available in a campaign only if the DM allows it. If the DM doesn't want it in the campaign, it simply doesn't exist.
    Smoke powder is commonly found divided into two separate components--one, a steely-blue granular substance, the other, a fine white powder. Alone, each component is inert and harmless. However, when equal portions of the two are mixed together, the smoke powder is complete and dangerous.
    When touched by a flame, the mixed powder explodes with great force, noise, and smoke. The size and force of the explosion varies according to the amount of smoke powder used. A small, measured amount (a spoonful of each component) causes 1d2 points of damage. Such an amount is sufficient for a large firecracker or a single charge of an arquebus (if these optional weapons exist in the campaign). Increasing the amount increases the damage proportionally--doubling causes 2d2 points of damage, tripling causes 3d2, and so on.
    An explosion capable of causing 10 points of damage (5 charges) have a 5-foot radius and those capable of 30 points of damage (15 charges) have a 10-foot radius. Blasts capable of causing 50 or more points of damage (25 or more charges) have a radius of 15 feet, and affect items and fortifications as would a giant's blow.
    When discovered, a pouch of smoke powder contains 3d6 charges. Charges from several pouches of smoke powder can be combined to create bigger, more damaging explosions. A single charge of smoke powder weights one ounce and 16 charges are 1 pound, and smoke powder is often sold in kegs and in water resistant powder horns. Small kegs have 15-pound capacity and 20 pounds total weight, and cost 1,200 gp (this assumes it is full to the brim with 240 charges)! Powder horns have 2-pound capacity and total weight, and cost 160 gp (this assumes it is full to the brim with 32 charges) for a full powder horn.
    Caster Level: 9th; Prerequisite: Craft Wondrous Item, 9+ ranks of Alchemy; Market Price: 5 gp per charge; Weight: 1 pound per 16 charges.
    Smoke power cost the Alchemist 4 gp per charge to make before reselling. While the cost of 5 gp per charge is what is most commonly charged for smoke powder, it not uncommon in areas where it is rare to see it as high as 25 gp per charge (increase the cost of small kegs and powder horns to match such inflated prices).

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Siege Weapons, © 1989, 1992 Wizards of the Coast, Inc. &
d20™ System, Conversion of Spelljamming Equipment to 3.5 ©2003, Mark T. Doolan
Original Sources:War Captain's Companion Boxed Set, Concordance of Arcane Space, SRD Equipment 1, and Spelljammer D20