What can you shoot with a ballista?

[Ahnehnois]

I have a shipboard crew with a mounted ballista on the foredeck. They wanted to shoot at a large-sized bird that was flying back and forth across the deck and attacking people. I said no, but I find no justification in the rules (SRD, also expanded and revised in Heroes of Battle). Am I missing something? Seems to me a ballista's utility should be substantially limited by size and mobility of the target (as should all weapons, siege weapons just seem a glaring example).

Anyone have any thoughts on what reasonable limitations to place on ballista fire?

 

[Theo R Cwithin]

By RAW, I'd go ahead and let them try to use it. Why not? (I don't know what HoB says on the matter, however.) [edit: apparently, historically, they were fairly accurate, too, at least according to wikipedia.]

It's already slow to fire, and there's already a -4 or -6 to the atk roll for PCs smaller than large. You might be justified in increasing those numbers a bit, since a ballista isn't just "a great big crossbow", it's actually bolted down, limited angles, etc. You could also certainly argue another -4 to atk for lack of proficiency.

If you factor in the fact that they might hit (and likely kill) a deckhand, or damage the boat if they miss, they might think twice about trying.

If you simply want to forbid it outright, how about an in-game reason? I don't know anything about ballistas, but you can say that the mount simply prevents it being aimed "backward" at the ship's deck/mast/etc; after all, it's designed to counter other boats, not threats on its own deck. Also, they're designed to fire "out" not "up", so if your bird is attacking with Flyby, kind of dive bombing and swooping back up, the ballista might not be able to point at a steep enough angle to aim at the bird. Or even, more simply, the PCs just can't find the bolts.

Not RAW solutions, but Rule 0 solutions!

 

[Nebten]

I've typically seen this as a rule set for ballistas:

Anyone can fire it, but it takes two full-round actions to reload, and Medium creatures take a –4 penalty to attack with it.​

So it allows the PCs one good shot with it, after that, if they want to spend 2 full round loading the bloody thing, let them do it. I doubt anybody would take that option unless they had the time to do so.

 

[Herobizkit]

If the bird is actually Large-size, chances are its manoeuvrability is average to poor... lots of time in between passes for folks to load up a ballista. After all, why give PC's a big gun if they can't use it?

 

[Ahnehnois]

Appreciate the replies, folks.

If you simply want to forbid it outright, how about an in-game reason? I don't know anything about ballistas, but you can say that the mount simply prevents it being aimed "backward" at the ship's deck/mast/etc; after all, it's designed to counter other boats, not threats on its own deck. Also, they're designed to fire "out" not "up", so if your bird is attacking with Flyby, kind of dive bombing and swooping back up, the ballista might not be able to point at a steep enough angle to aim at the bird. Or even, more simply, the PCs just can't find the bolts.

Not RAW solutions, but Rule 0 solutions!

I would imagine that in this circumstance, the ballista would not have been able to turn far enough up to hit it, perhaps. The bird was flybying.

So it allows the PCs one good shot with it, after that, if they want to spend 2 full round loading the bloody thing, let them do it. I doubt anybody would take that option unless they had the time to do so.

Two operators can both use a full-round action simultaneously, so it takes only one round of time to reload, as explained in HoB. In my circumstance, the characters wanting to operate it were useless in battle otherwise; the PC officers certainly would not have done this.

If the bird is actually Large-size, chances are its manoeuvrability is average to poor... lots of time in between passes for folks to load up a ballista. After all, why give PC's a big gun if they can't use it?

Maneuverability was average, I think. It just seems hard to imagine the turntable rotating fast enough to hit a moving target. To me they'd have had to anticipated its movement, set up for one area, and shot when it moved in there. Which takes a lot more luck and skill than a regular attack roll.

The reason I gave them a ballista is to shoot it at other ships, which would be far away and slow-moving.

 

[NewJeffCT]

The reason I gave them a ballista is to shoot it at other ships, which would be far away and slow-moving.

A shipboard ballista will likely have pretty good maneuverability - it will have to be able to fire at a relatively flat angle for long distance as an enemy ship closes with it, but it would also be able to rotate up to fire at close range - i.e., fire a flaming bolt or a chain into the other ship's rigging as they are broadsides from each other. (there is a 3rd party book that even has a ballista that can be adapted to be a chainflinger) If operated by a single person, I would stick with giving them a -4 penalty to hit - but, I would also drop it down by -2 for each person helping out in terms of loading, aiming, positioning. Of course, that also means two PCs or three are doing the aiming and not shooting a crossbow or firing off a spell.

Additionally, if you are gaming in anything but a low magic world without a lot of fantastical monsters, the ballista would almost certainly be able to rotate to fire up at a pretty good angle, as ships would have to be able to defend themselves from an aerial attack from flying monsters or people with fly spells on them. I'm not saying it would fire straight up into the air at a dive bombing dragon, but I would allow it to fire at anything coming in at a 60 degree angle or less.

And, I would think the PCs could take a ready action to fire the ballista when the bird closes.

 

[Mark1733]

I would say that only two people can attempt to use it...any more people will simply get in the way. Penalties apply as -4, because it's rusty or otherwise in need of some maintenance. However, what if they have true strike?

Another option is to give them some other stuff to consider being more creative with it. For example, is there a fishing net or old sail that they can launch with it and snare the bird instead? Can it be modified to shoot a tanglefoot bag or something other than a bolt?

Does this thing also act as the harpooning gun? Maybe it is more for a water creature that reaches up out of the water and attacks the bird as well...now there is huge 3-way battle.

 

[Ogrork the Mighty]

Keep in mind that ballista were used by the Romans to clear parapets of enemy troops. So targets don't necessarily have to be big or slow moving.

 

[Herobizkit]

And, just to be glib, what CAN'T you shoot with a ballista?

 

[Dandu]

You can sneak attack people with Ballistas.

I saw it in The Gamers.