Magic Siege Engines

Siege engines can be enhanced by magic through the use of the Craft Magic Arms and Armor feat. Magic siege engines and siege ammunition can have enhancement bonuses ranging from +1 to +5. These bonuses apply on attack rolls, as well as on skill checks for operating a catapult.

All magic siege engines are also masterwork siege engines. The enhancement bonus from the masterwork quality does not stack with any magical enhancement bonus.

In addition to an enhancement bonus, siege engines can have special abilities. Special abilities count as additional bonuses for determining the market value of the item, but they do not modify attack bonuses or skill check modifiers (except where noted). A single siege engine may not have a modified bonus (enhancement bonus plus special ability bonus equivalents) higher than +10. In order to have a special ability, an engine must have at least a +1 enhancement bonus.

Siege Weapon Ammunition: Unlike normal ammunition, magic siege weapon ammunition is priced individually (not in lots of 50).

The enhancement bonus from a siege weapon does not stack with the enhancement bonus from ammunition. Only the higher of the two bonuses applies.

Ammunition fired from a siege weapon with an enhancement bonus or an alignment is treated as a magic weapon or an aligned weapon for the purpose of overcoming damage reduction, just as with other ammunition.

After a piece of magic siege ammunition has been used, it loses any magical powers it had, regardless of whether it hits or misses or if the ammunition can be recovered.

Siege Engine Magical Bonuses
Weapon BonusBase Price
+12,000 gp
+28,000 gp
+318,000 gp
+432,000 gp
+550,000 gp
+6¹72,000 gp
+7¹98,000 gp
+8¹128,000 gp
+9¹162,000 gp
+10¹200,000 gp
¹ Magic siege engines can't actually have bonuses this high. Use these lines to determine price when special abilities are added in. Example: A +5 light ballista that also has the disruption special ability (see below) is treated as a +7 light ballista for pricing purposes and is priced at 98,000 gp.
WeaponWeapon Cost¹
Ammunition+300 gp
Ballista, light+1,000 gp
Ballista, heavy+2,000 gp
Mangonel, light+1,100 gp
Mangonel, heavy+1 600 gp
Scorpion+2,500 gp
Trebuchet, light+3,000 gp
Trebuchet, heavy+6,000 gp
¹ Add to enhancement bonus above to determine total market price.
Siege Engine Special Abilities
Special AbilityBase Price Modifier¹
Necromantic+3,000 gp
Disrupting+2 bonus
Self-loading+2 bonus
Starburst+2 bonus
¹ Add to enhancement bonus above to determine total market price.

Magic Siege Engine Special Ability Descriptions

In addition to enhancement bonuses, siege engines can have one or more of the special abilities detailed below or any of those described for ranged weapons in Magic Weapon Abilities (except for speed). A siege engine with a special ability must have at least a +1 enhancement bonus.

Disrupting: In addition to dealing its normal damage, a projectile from a disrupting siege weapon can destroy undead creatures within 60 feet of the impact. Treat this effect as if the projectile had performed a turning check as a 5th-level cleric (the projectile has no Charisma modifier). Undead that would be turned by the check are unaffected, but any undead that would be destroyed by the check are destroyed. Undead closest to the impact spot are affected first.
Moderate transmutation; Cl 5th; Craft Magic Arms And Armor, ability to turn undead; Price +2 bonus.

Necromantic: In addition to dealing its normal damage, a projectile from a necromantic siege weapon animates dead creatures within 60 feet of the impact spot, turning them into zombies for the next 10 rounds. A single necromantic projectile can create up to 20 HD of zombies. The undead created by a necromantic projectile are uncontrolled and will attack the nearest living creature.
Faint necromancy; Cl 10th; Craft Magic Arms And Armor; Animate Legion; Price +3,000 gp.

Self-Loading: A self-loading siege weapon automatically winches the throwing arm back into firing position and loads the next projectile in line. This replaces the Strength check and Profession (siege engineer) check required to reload a weapon and reduces the time needed to load a siege weapon by one full-round action (to a minimum of one full-round action).
Strong transmutation; Cl 11th; Craft Magic Arms And Armor; Telekinesis; Price +2 bonus.

Starburst: Stones fired from a starburst siege weapon explode above the ground, spraying the area below with a deadly shower of rock fragments. A stone fired from a starburst siege weapon deals piercing and slashing damage (equal to its normal damage) to all creatures within 20 feet of the impact square (Reflex DC 15 half).
Moderate abjuration; Cl 7th; Craft Magic Arms And Armor; Stone Shape; Price +2 bonus.

Specific Siege Engines and Ammunition

The following specific siege weapons and ammunition usually are constructed with exactly the qualities described here.

Acid Stone: This spherical clay ball is filled with acid. It deals 1d6 points of bludgeoning damage to its target. In addition, upon impact it breaks apart, dealing 2d6 points of acid damage to any creature or object in the square it hits and 1d6 points of acid damage to any creature or object in an adjacent square.

Alchemist's Stone: This spherical clay ball is filled with alchemist's fire. It deals 1d6 points of bludgeoning damage to its target. In addition, upon impact it breaks apart, dealing 2d6 points of fire damage to any creature or object in the square it hits and 1d6 points of fire damage to any creature or object in an adjacent square. Any creature or object exposed to the alchemist's fire also catches fire; creatures and attended objects can avoid this by succeeding on a DC 15 Reflex save.

Battering Ram, Adamantine: A bane to any gate or wall that stands in its way, the adamantine rain ignores hardness of less than 20 possessed by any object it strikes. With an adamantine head cast in the likeness of a mountain ram, this is an expensive but effective way of breaking down barriers.
No aura (nonmagical); Price 16,000 gp.

Ballista Bolt, Adamantine: An adamantine ballista bolt ignores hardness of less than 20 possessed by any object it strikes.
No aura (nonmagical); Price 3,001 gp.

Catapult Stone, Adamantine: Though most weaponsmiths would decry this as an inexcusable waste of precious metal, there is no doubt as to the effectiveness of a huge chunk of adamantine thrown from a catapult. An adamantine catapult stone ignores hardness of less than 20 possessed by any object it strikes.
No aura (nonmagical); Price +100 gp/lb. (see Siege Engines.)

Dragonfire Ram: The head of this battering ram depicts a fearsome dragon in mid-breath. The dragon's mouth flickers with fire, and each blow of the ram sends flaming embers flying. Each strike of the rain deals an extra 1d6 points of fire damage to any wooden or flammable object it strikes, ignoring hardness. If the ram breaks through the object it strikes, it immediately breathes a 30-foot cone of fire through the opening, dealing 2d6 points of fire damage (Reflex DC 15 half). It can breathe fire once per day.
Faint evocation; Cl 3rd; Craft Magic Arms And Armor, Scorching Ray; Price 4,000 gp.

Dragonshot Catapult: A dragonshot catapult appears much like a typical catapult bearing an elaborate rendition of a dragon's head at the end of the throwing arm. Instead of loading normal shot or stone, the operator can choose to load a gemstone of the appropriate type and value listed below. Activating the firing mechanism hurls the gemstone as if it were a stone appropriately sized for the catapult. When the gemstone strikes the ground, it explodes in a burst of energy. All nearby creatures and objects take damage as detailed below:

Strong transmutation; Cl 15th; Craft Magic Arms And Armor; Price +10,000 gp.

Elemental Rockshot: This ordinary-looking catapult stone can be fired from a scorpion or heavy mangonel. After it impacts (dealing damage as normal), elemental rockshot transforms into a Small earth elemental, attacking nearby enemies for 5 rounds before crumbling into dust.
Faint conjuration; Cl 5th; Craft Wondrous Item, Summon Monster III or Summon Nature's Ally II; Price 750 gp.

Hellwasp Shot: This ammunition resembles a hardened mound of mud and can be loaded into any stone-throwing catapult. On impact, hellwasp shot deals no damage but instead breaks open and spews out a magically summoned swarm of hellwasps. The swarm fills a 10-foot cube and attacks all creatures within that area for 10 rounds before disappearing. If hellwasp shot lands in a unit of creatures of 6 HD or less, it forces a morale check (see Morale).
Moderate conjuration; Cl 10th; Craft Magic Arms And Armor, Summon Monster V; Price 2,500 gp.

Holy/Unholy Stone: This spherical clay ball is filled with the equivalent of five flasks of holy or unholy water. It deals 1d6 points of bludgeoning damage to its target. In addition, it breaks apart upon impact, allowing the holy stone version to deal 4d4 points of damage to any undead creature or evil outsider in the square it hits, and 2d4 points of damage to any such creature in an adjacent square. An unholy stone deals the same amount of damage to good outsiders.

Lightning Ballista: This magic light ballista does not use traditional ammunition. Instead, it fires a 60-foot line of lightning when triggered. Creatures in the path of the bolt take 5d6 points of electricity damage (Reflex DC 14 half). A lightning ballista can be fired only once per minute (except in a stormy environment, where it can be fired every other round). A lightning ballista requires no loading time or attack roll.
Moderate evocation; Cl 5th; Craft Magic Arms And Armor, Lightning Bolt; Price 15,000 gp.

Scorching Ballista: This magic light ballista does not use traditional ammunition. Instead, it fires a 60-foot ray of fire when triggered. The operator of a scorching ballista makes an attack roll as normal for firing a ballista; however, he need only succeed on a ranged touch attack to strike his target. A target hit by the ray takes 4d6 points of fire damage. A scorching ballista can be fired only once per minute but requires no loading time.
Faint evocation; Cl 3rd; Craft Magic Arms And Armor, Scorching Ray; Price 6,000 gp.

Self-Launching Stone: A self-launching stone provides all the benefit of a catapult, without the trouble of constructing or maintaining a machine. On command, a self-launching stone flies into the air and strikes as if fired from a light mangonel, automatically hitting the target square. A self-launching stone only functions once, just like other magic siege weapon ammunition.
Moderate transmutation; Cl 9th; Craft Magic Arms And Armor, Telekinesis; Price 500 gp.

Spider Shot: This clay pot is filled with hundreds of venomous spiders and sealed with a large cork stopper. It deals 1d6 points of bludgeoning damage to its target. In addition, the contents spread over a 10-foot-by-10-foot square, creating a spider swarm. This swarm attacks all creatures in or adjacent to its space but does not attack any creatures more than 5 feet away.

Tanglefoot Shot: This ammunition is essentially an enormous tanglefoot bag. It deals no damage to its target. Instead, all creatures within 5 feet of the impact square are affected as if they had come into contact with a tanglefoot bag (see Special Items); the creature in the impact square takes a -5 penalty on its save to avoid being glued to the floor.

Specific Siege Weapons And Ammunition
Special AmmunitionPriceWeight
Acid stone¹²50 gplOb.
Alchemist's stone¹²100 gp10 lb.
Catapult stone, adamantine+100 gp/lb.40-150 lb.
Holy/unholy stone¹²]25 gp10 lb.
Tanglefoot shot²250 gp20 lb.
Spider shot¹²300 gp10 lb.
Self-launching stone500 gp40 lb.
Elemental rockshot750 gp75 lb.
Hellwasp shot²2,500 gp20 lb.
Ballista bolt, adamantine3,001 gp6 lb.
Dragonfire ram4,000 gp3,000 lb.
Scorching ballista6,000 gp400 lb.
Dragonshot catapult10,000 gp2,000 lb.
Lightning ballista15,000 gp400 lb.
Battering ram, adamantine16,000 gp3,000 lb.
¹In addition to any normal Craft (alchemy) check required to create the appropriate substance, each of these items requires a DC 10 Craft (pottery) check to manufacture the vessel.
² Unless otherwise noted, these items can be fired only by a catapult capable of firing stones or shot.

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