(PF) Explosives

[Slylizard]

Howdy, I've got a player (alchemist) in a pathfinder game who wants to try their hand at dynamite (or some sort of wall busting equivalent).

What I'd like to create (and am having troubles pulling off) is how to make this happen.

I'm trying to have something that basically does the following:
1. Has a long fuse (thus making it useless in combat); and
2. Does enough damage to blow a standard wall (masonry wall would mean 98 damage) more often than not... call it a 90% chance to succeed.

Any takers to help out?

[Debihuman]

A single stick of dynamite isn't that powerful and going by the MSRD, it does 2d6 points of damage and has a 10-foot range. Here is a decent 3.5 conversion:
http://www.obsidianportal.com/campaigns/mission-from-sigil/items/dynamite

Dynamite:
This short, thin cylinder of explosive material has a fuse that must be lit before it is thrown or set. Lighting a stick of dynamite is a move action, and the dynamite goes off in the same round or up to several minutes later (depending on how long the fuse is). The explosive has a blast radius of 5 feet and deals 2d6 points of bludgeoning damage. Anyone caught within the blast radius can make a DC 15 Reflex save to take half damage.
It’s possible to bind together several sticks of dynamite so they ignite and explode at the same time. Each additional stick increases the damage by 1d6 (maximum damage 10d6) and the burst radius by 5 feet (maximum burst radius 20 feet).

[SamBurke]

Honestly, that's really sub-par for the rules as given.

The thing I'd say is balance it the way it's balanced in the real world: it takes a long time to make.

[Debihuman]

Honestly, that's really sub-par for the rules as given.

Here are the rest of the rule from the MSRD:


Dynamite: Perhaps one of the most common and straightforward explosives, dynamite is very stable under normal conditions. A stick of dynamite requires a fuse or detonator to set it off. Additional sticks can be set off at the same time if they are within the burst radius of the first stick, increasing the damage and burst radius of the explosion. Each additional stick increases the damage by +1d6 (maximum 10d6) and the burst radius by 5 feet (maximum 20 feet).

It’s possible to wire together several sticks of dynamite for even greater explosive effect. Doing so requires a Demolitions check (DC 10 + 1 per stick). If the character succeeds on the check, the damage or the burst radius of the explosion increases by 50% (the character’s choice).

Dynamite is sold in boxes of 12 sticks. It is considered to be a simple explosive for the purpose of using a Craft (chemical) check to manufacture it.

To set off dynamite using a fuse, the fuse must first be lit, requiring a move action (and a lighter or other source of flame). The amount of time until the dynamite explodes depends on the length of the fuse—a fuse can be cut short enough for the dynamite to detonate in the same round (allowing it to be used much like a grenade), or long enough to take several minutes to detonate. Cutting the fuse to the appropriate length requires a move action.


What are you finding "sub par" about the dynamite?

Debby

[Slylizard]

What are you finding "sub par" about the dynamite?


I'd tend to agree that it's a bit sub-par. To put it in perspective (assuming average damage) it would take 28 sticks of dynamite to blow a 1ft thick masonry wall if you simply put them together.

If you tried to wire them for greater effect, and selected the 50% extra damage it would still take 19 sticks (average of 66.5 damage, increased by 50% to 99.75) and a DC 29 demolitions check.

It seems like we're using far too much explosives for the damage outcome here.

What I was thinking was a bit simpler, but wasn't sure it was workable, let alone how to price it. The explosive would do:
- 3D6 damage with a blast radius of 10ft, DC14 ref save for half
- Bonus 90 damage on stationary targets
- 5+D6 round fuse
- DC20 Craft Alchemy check to make
- ??? gold to craft

Makes it pretty useless in combat, as people can move away very easily (especially with the long fuse timer). Makes it risky to use in general as you don't know how long it's going to take before blowing (thus doesn't become the instant in and out avenue), and you only have an 84% chance of it getting through with a single stick.

I'd also give it a 10% chance to blow should the carrier get hit with fire (such as from the fireball spell). Just so they don't carry around 10 dozen sticks.

Thoughts?

[eftexar]

The problem is that PF/D&D doesn't scale the same way as the real world. I would say Debihuman's post sums up a fairly well balanced representation within the game world, though it could probably afford to ignore hardness.

What you might consider, instead of just increasing damage, is to modify Debihuman's version so that it has a chance of simply breaking objects regardless of damage.

With some modifications we have something like this:


Dynamite
Dynamite is sold in boxes of 12 sticks. It is considered to be a simple explosive for the purpose of using a Craft (chemical) check to manufacture it. A stick of dynamite requires a fuse or detonator to set it off.

Perhaps one of the most common and straightforward explosives, dynamite is very stable under normal conditions. A character caught within the area of a fire, or electricity effect, risks a 20% of any dynamite they are carrying of being set off. A reflex save, DC 16 + 1 per stick (maximum of 25), halves this damage.

A single stick deals 1d6 damage, half bludgeoning and fire, in a 5ft radius explosion, ignoring any hardness objects caught within might have. Furthermore, this blast makes a strength check, with a +12 modifier, in an attempt to break any un-attanded objects within it's area. Against easily flammable objects, such as rope or wood, this check is increased by +6 (not counted towards the maximum).

Additional sticks can be set off at the same time if they are within the burst radius of the first stick, increasing the damage and burst radius of the explosion.
Each additional stick increases the damage by +1d6 (maximum 10d6), the burst radius by 5 feet (maximum 20 feet), and the modifier for the strength check by +2 (maximum modifier of 30).

To set off dynamite using a fuse, the fuse must first be lit, requiring a move action (and a lighter or other source of flame).

The amount of time until the dynamite explodes depends on the length of the fuse—a fuse can be cut short enough for the dynamite to detonate in the same round (allowing it to be used much like a grenade), or long enough to take several minutes to detonate. Cutting the fuse to the appropriate length requires a move action.

Cutting the fuse requires a Demolitions check, at DC of 10 + 2 per round of delay, be made. Failure results in the detonation being delayed by 1d4 rounds beyond that intended.

[Slylizard]

That's a really good tweak, I like that. The strength check was something I didn't even think of but is a pretty elegant way to pull it off.

I think I might run with that, just need to determine a craft DC and cost as the player in question is an alchemist, so it makes sense that he could make it himself.

[TuggyNE]

The idea for a Str check is good, since dynamite actually works mostly by sudden pressure (gasoline has more total chemical energy than almost any explosive), but the numbers are still off; +12 against a DC of 35 means a single stick of dynamite is incapable of blowing through a 1' masonry wall. Period.

Crank it up to at least +20, and note that the damage is done before the Str check (which will sometimes drop the DC by 2), and you might have something; a single stick will get through about 30% of the time. Actually, that might still be too low, so maybe I should go research some more concrete numbers. (It shouldn't ignore hardness, though, I think.)

[LordErebus12]

an M80 held in an open hand (in rl) will burn the hand and tear skin but will not be as severe as if it were held in a closed hand. you will lose the hand, rather than simply burning/ripping it. this is a fact

the two examples i give is my father, who lost skin and part of a finger from one going off as he let it go from his hand. it blew up about a second from his hand.
as opposed to my old friend jim, who lost a hand many years ago with the same powered m80 as he lit it while still tightly holding it.

so perhaps something like:

when dynamite (or any other high explosive) is contained and unable to fully expand (say in a predrilled hole or in a tightly closed fist), the damage is doubled. furthermore, it reduces the hardness of an object by half.

the shockwave from the blast should act a bit like sonic damage, imo; ignoring hardness if contained within a small spot, while dealing much more intense damage overall as the force of it rips through the object.

[LordErebus12]

Id also like to point out that a fireball or burning hands spell could pretty much instantly kill your alchemist friend, lighting his entire stash of explosives off at once.

rather like the necklace of fireballs.

If the necklace is being worn or carried by a character who fails her saving throw against a magical fire attack, the item must make a saving throw as well (with a save bonus of +7). If the necklace fails to save, all its remaining spheres detonate simultaneously, often with regrettable consequences for the wearer.

[Debihuman]

Masonry walls have the same stats in as cinder-block walls in d20 Modern. Both are one foot thick, have a break DC of 35, Hardness 8, and 90 hp for a 10-ft.-by-10-ft. section.

And I just learned something about the Demolitions check: "With a successful Demolitions check (DC 10 +1 per stick), a character may increase the total damage, or the total radius, by 50%. Thus, a character who throws nine sticks of dynamite in a bag and sets them off with another gets a 10d6 explosion with a 20-foot radius. If that character takes the trouble to wire them together with a DC 19 Demolitions check, he can have either a 15d6 explosion with a 20-foot radius, or a 10d6 explosion with a 30-foot radius."

15d6 may not be enough to take down the whole wall, but it will take out 52 hps worth on average, which is half the wall. And it's better than a fireball now.

Alchemist's fire doesn't cause an explosion, it just burns stuff.

If you are playing in a Medieval-like setting, I'm not entirely convinced that explosives (other than gunpowder) would be even available. The major problem with using gunpowder as an explosive devise is the soot. Everything would be coated with soot.

An 800 gp heavy catapult would be a lot cheaper and easier to use and would probably do a better job. See here towards the bottom of the page: http://www.d20srd.org/srd/wilderness.htm

[LordErebus12]

15d6 may not be enough to take down the whole wall, but it will take out 52 hps worth on average, which is half the wall. And it's better than a fireball now.

Debby

its better if you use a fireball to set off the 15d6 dynamite in the first place.

[Slylizard]

If you are playing in a Medieval-like setting, I'm not entirely convinced that explosives (other than gunpowder) would be even available. The major problem with using gunpowder as an explosive devise is the soot. Everything would be coated with soot.

An 800 gp heavy catapult would be a lot cheaper and easier to use and would probably do a better job. See here towards the bottom of the page: http://www.d20srd.org/srd/wilderness.htm

I understand this entirely, hence I've been a little reluctant in allowing it. However, he's explained the uses he wants it for (breaching walls for interesting attack angles and the like) and to be honest it sounds like it opens the group up for a little more fun. Who am I to stop them having fun?

I'm basically fluffing it like highly packed gunpowder in a tube. Being that gunpowder is available (the gunslinger for example) I can handle that extension.

Yeah the catapault is easier in the sense of it works... but a lot less viable in the fact that they can't really take it with them everywhere :P

I'm also happy with the possibility that a fire/electircity attack blows the alchemist up. It means he needs to balance the risk of carrying around these things against his safety. Really it'll just mean that he won't carry too many because it'll be too risky (and thus control how out of hand he might get with them).

At the moment I'm running with the below taking into account LordErebus12's comments about contained explosions. Giving it a craft DC of 20, and making the materials cost 500gp:


Dynamite
It is considered to be a simple explosive for the purpose of using a Craft (Alchemy) check to manufacture it. A stick of dynamite requires a fuse or detonator to set it off.

Perhaps one of the most common and straightforward explosives, dynamite is very stable under normal conditions. A character caught within the area of a fire, or electricity effect, risks a 20% of any dynamite they are carrying of being set off. A reflex save, DC 16 + 1 per stick (maximum of 25), halves this damage.

A single stick deals 1d6 damage, half bludgeoning and fire, in a 5ft radius explosion, ignoring any hardness objects caught within might have. Furthermore, this blast makes a strength check, with a +16 modifier, in an attempt to break any un-attanded objects within its area (object STR DCs found here). Against easily flammable objects, such as rope or wood, this check is increased by +6 (not counted towards the maximum).

Additional sticks can be set off at the same time if they are within the burst radius of the first stick, increasing the damage and burst radius of the explosion. Each additional stick increases the damage by +1d6 (maximum 10d6), the burst radius by 5 feet (maximum 20 feet), and the modifier for the strength check by +2 (maximum modifier of 30). An explosion that is enclosed within an area (such as drilled into a wall) will double the strength check bonus granted.

To set off dynamite using a fuse, the fuse must first be lit, requiring a move action (and a lighter or other source of flame).

The amount of time until the dynamite explodes depends on the length of the fuse—a fuse can be cut short enough for the dynamite to detonate in the same round (allowing it to be used much like a grenade), or long enough to take several minutes to detonate. Cutting the fuse to the appropriate length requires a move action.

Cutting the fuse requires a Craft (Alchemy) check, at DC of 10 + 2 per round of delay, be made. Failure results in the detonation being delayed by 1d4 rounds beyond that intended.

Thanks for the help all!

[LordErebus12]

I'm basically fluffing it like highly packed gunpowder in a tube. Being that gunpowder is available (the gunslinger for example) I can handle that extension.

Giving it a craft DC of 20, and making the materials cost 500gp:



Thanks for the help all!

Just remember, no gunpowder is actually used in dynamite.

Classic dynamite consists of three parts nitroglycerin, one part diatomaceous earth and a small admixture of sodium carbonate. This mixture is formed into short sticks and wrapped in paper. Nitroglycerin by itself is a very strong explosive, and in its pure form it is extremely shock-sensitive (that is, physical shock can cause it to explode), and degrades over time to even more unstable forms. This makes it highly dangerous to transport or use in its pure form.

Absorbed into diatomaceous earth or sawdust, nitroglycerin is less shock-sensitive. Over time, the dynamite will "weep" or "sweat" its nitroglycerin, which can then pool in the bottom of the box or storage area. (For that reason, explosive manuals recommend the repeated turning over boxes of dynamite in storage.) Crystals will form on the outside of the sticks causing them to be even more shock, friction or temperature sensitive. This creates a very dangerous situation. While the possibility of explosion without a blasting cap is minimal, old dynamite is extremely dangerous.

Dynamite is usually sold in the form of cylinders about 8 in (20 cm) long and about 1.25 in (3.2 cm) in diameter, with a weight of about 0.5 lb troy (0.186 kg). Other sizes also exist. The maximum shelf life of nitroglycerin-based dynamite is recommended as one year from the date of manufacture under good storage conditions.

Another form of dynamite consists of nitroglycerin dissolved in nitrocellulose and a small amount of ketone. This form of dynamite is similar to cordite, and is much safer than the simple mix of nitroglycerin and diatomaceous earth. Military dynamite achieves greater stability by avoiding the use of nitroglycerin and uses much more stable chemicals.

id say DC 20 might be a bit low, imo. perhaps if it takes multiple steps to make, like it does in real life, with multiple checks of DC 20. you're gonna have to keep checking it so it doesn't go boom.

Basically... good luck to you, sir :smallbiggrin:

[Slylizard]

Yeah, I realise the reskinning isn't overly accurate, but considering we're playing a game with magic and dragons I can handle that little extension :P

I'll take the DC note on board and might play with that. Appreciate the help!