rules for ballistas?

[Braininthejar2]

Where can one find good rules for ballistas? Are they anything beyond sized-up crossbows?

(the GoT finale made me think, D&D ballistas would probably be useless against dragons, even if there is a hero aiming one with sufficient BAB... )

[inuyasha]

3.5 has ballistae and other siege engines here, and if you want a few more variations there are some cool siege engines and alternate ballista designs here for Pathfinder.

I believe there are also some more in the Stronghold Builder's Guidebook because of its focus on architecture and smashing it to pieces, and maybe more still in Heroes of Battle which focuses on mass combat. But I'm not entirely sure.

[RNightstalker]

Heroes of Battle has some magic improvements for ballistae.

[gorfnab]

Through some minor shenanigans and DM hand-waving you could just wield a makeshift ballista using the following setup.

Items:
Strongarm Bracers (MIC)
+1 Large Aptitude (ToB) Great Crossbow (RoS)

Feat:
Hand Crossbow Focus (DoTU)

Class:
Targeteer Fighter ACF (Drg #310) or regular Fighter if Dragon Magazine is not available

Setup:
Targeteer Fighter gives you proficiency in a number of Exotic ranged weapons of your choosing at first level. You'll need to choose Hand Crossbow and Great Crossbow for this build. Choose Arrow Swarm as your Targeteer Ability. If Dragon Magazine material is not available, then you can just take a level or two of Fighter (or just any class and use up your normal feats) and choose the Exotic Weapon Proficiency feats for those two crossbows instead. A slightly loose interpretation of the Aptitude magic weapon enhancement ability and the feat Hand Crossbow Focus leads to a situation when combined with a Great Crossbow where you can get iterative attacks in a round with the Great Crossbow (through free action reloading as if it were a Hand Crossbow). Strongarm Bracers ups this interesting situation by making you able to wield a Large size Great Crossbow, basically a ballista (with 3d8 damage instead of the normal ballista damage of 3d6).

[Mnemius]

I think I've heard about some half-joking, half-serious talk about characters in pathfinder wielding ballista as weapons... And at least one DM shot my bard in his campaign with a siege weapon. (It hurt, but I lived.)

[Braininthejar2]

3.5 has ballistae and other siege engines here, and if you want a few more variations there are some cool siege engines and alternate ballista designs here for Pathfinder.

Yup, straight 3d8, no strength bonus.

There is a picture in one of the books with heroes goading a dragon, with a ballista aimed point blank outside its lair, but it would likely not beat its AC, and even then make it angry at most.

[Eldariel]

Yup, straight 3d8, no strength bonus.

There is a picture in one of the books with heroes goading a dragon, with a ballista aimed point blank outside its lair, but it would likely not beat its AC, and even then make it angry at most.

Indeed, the main issue is that weapon damage is of rather minor importance in 3.5 and that's all siege engines get. One skilled archer with a bow can put out a dozen ballista's worth of damage in a turn alone.

[upho]

I think the only potential exceptions when it comes to siege weapons are the two size Large and Huge direct fire firearm ones in PF (ie the cannon and fiend's mouth cannon), as they can actually be quite silly in the right combo (that is a gunsmoke mystic with expansion/metamorphosis plus Vital Strike). I mean attack vs touch AC within 300+ ft. for more than 256d6 damage silly...

[Braininthejar2]

I think, since crossbows use their own strength, a ballista should have a strength bonus from size to damage.