|Image from Wikipedia|
Also known as gatecrashers, petards are incendiaries designed to blow open doors or other small fortifications. Petards are second level concoctions, and thus cost 1000 GP in components in addition to special ingredients, given a functional recipe. One recipe involves ash that was used in the ritual to summon a fire elemental.
Petards are designed to be more targeted than firebombs, and also use slow fuses, so they are not as effective in direct combat (though they can make excellent diversions or surprise attacks, if used tactically). The standard, and safest, use of a petard uses a full slow fuse and takes one turn. The fuse may also be trimmed for faster detonation (within 1d6 combat rounds; on a roll of 1 the detonation is premature and the petardier is caught in the blast). Any standard (even reinforced) door will be blown open by a petard charge. Solid metal doors will be blown on 3 in 6 and stone doors on 1 in 6. Anyone within 10′ of a petard detonation takes 2 dice of damage (save for half).
Longer fuses may be used, but for each turn worth of extension there is a 1 in 6 chance the fuse will go out before it reaches the petard. For example, a petard with a 4 turn fuse has a 3 in 6 chance of not detonating. Stacked petards will blow each other, but will never do more than one extra die of damage (so 10 petards results in 10 chances to blow a door but only 3 dice of damage).
It seems like this would be a more reliable (though more noisy) way to open locked doors.
Though I suppose this has a much higher cost than lockpicking.
Don’t forget that there exist secured doors without locks that one might still nevertheless desire to bypass (barred doors, drawbridges, etc). Also you might be able to deposit a petard against a door without approaching it (via 10′ pole or something else).
I am curious about these costs. Now Magic research is expensive – but it’s a permanent gain. A one use door knocker for 1,000 GP seems really high. Given that a 2nd level fighter will have 2,000 GP, I can’t see anyone bothering to make this item till some time much later.
I mean maybe 1,000 GP for research and then costs akin to scroll prep costs?
Well, my thoughts are as follows.
1. Anyone can use them after they are made. So they are more versatile than scrolls, which require a magic-user with read magic.
2. It seems like there are lots of other uses than just blowing doors, though that is the most common reason for their creation within the world.
3. It seems to be about right in terms of utility compared to potions. Those are also 500 or 1000+ GP for a single use effect. It’s true that 900 GP for 3 third level scrolls is probably a better deal, but then scrolls are kind of what magic-users do, whereas incendiaries are more peripheral for fighters.
4. Even if people don’t end up making them directly (we’ll see how the incentives work out), they can be found as interesting items within game, and sold as treasure.
5. I see initial research as finding or buying the recipe, which would potentially be a further cost.
If the cost ends up being too high, I would probably rather increase the utility rather than decrease the cost to maintain the symmetry with potion creation. Perhaps something like 1d6 units created per “potion” (actually, that’s already how I have poison creation working, so that’s what I would probably do here too).
Hmm, now I’m leaning towards making incendiaries 1d6 per batch preemptively. I do want people to use these things!
Yeah batch wise seems smart-100gp each matches poison cost (for that paralytic say). You can always limit availability with special ingredients.