Rate my "Big Bad Evils"

[DocRailgun]

Because the OP asked that this sort of stuff be rated/discussed. This is the GURPS forum, where everything (even fantasy and sci-fi) is expected to be reasonable if not realistic. Elaborate backstories (especiaaly cinematic ones) are going to get picked apart for their basic assumptions.

Originally Posted by Maz

Because thats much more realistic than super corrosive ant acid?
Honestly why are people even trying to limit thia to what is realistic?

[Alonsua]

Originally Posted by DocRailgun

Because the OP asked that this sort of stuff be rated/discussed. This is the GURPS forum, where everything (even fantasy and sci-fi) is expected to be reasonable if not realistic. Elaborate backstories (especiaaly cinematic ones) are going to get picked apart for their basic assumptions.

Yes, that´s fine and I want it to happen, but as I said, these ants can sting for up to 0.75 liters, so we're not talking about just small ant bites and less than a milligram of toxins. They can literally spill a whole bottle of acid and venom with a single bite. And they would not waste such a precious gift if they did not know for sure that it is going to enter directly into your body or your blood flow, where less than 5 liters of blood nourish your body. So up to 15% of the content of your blood could be formic acid and other toxins by now. Would that feel right?

[Alonsua]

Anybody calls for insta-heart attack or agony instead of terrible pain?

[AlexanderHowl]

Originally Posted by Alonsua

How many miligrams/mililiters are we talking here? Because these ants can sting for up to 750g (0.75 liters) (thats the total content of their sack, so they would rather not), and so far I thought the lethal dose was about 18.75g for a 125 lbs person.

A gallon of acid causes 8 points of corrosive damage before neutralization (Magic, p. 184). The attack that the ant is trying to do (maximum base damage of 35 corrosive damage) would require over 4 gallons of formic acid, which would weigh more than the giant ant. That is why the attack is unrealistic.

It is also impossible to deliver such an attack directly into the blood stream (if you assume 750 grams). The poison glands would likely have a crosssection of 1 mm, which would mean that they would need to deliver the acid at 750 meters per second to deliver all of the acid in one bite to the blood stream. With that much force, the recoil would blow the head of the ant off at 150 meters per second.

It is really a moot point through, as the bite should probably cause toxic damage rather than corrosive damage. A toxic attack can easily cause that level of damage (it is the equivalent of around 1 gram of king cobra venom) because poisons kill by disabling biological processes rather than killing by turning someone to a pile of goo. If you change the attack to a toxic attack, it will be fine.

[Alonsua]

Originally Posted by AlexanderHowl

A gallon of acid causes 8 points of corrosive damage before neutralization (Magic, p. 184). The attack that the ant is trying to do (maximum base damage of 35 corrosive damage) would require over 4 gallons of formic acid, which would weigh more than the giant ant. That is why the attack is unrealistic.

It is also impossible to deliver such an attack directly into the blood stream (if you assume 750 grams). The poison glands would likely have a crosssection of 1 mm, which would mean that they would need to deliver the acid at 750 meters per second to deliver all of the acid in one bite to the blood stream. With that much force, the recoil would blow the head of the ant off at 150 meters per second.

It is really a moot point through, as the bite should probably cause toxic damage rather than corrosive damage. A toxic attack can easily cause that level of damage (it is the equivalent of around 1 gram of king cobra venom) because poisons kill by disabling biological processes rather than killing by turning someone to a pile of goo. If you change the attack to a toxic attack, it will be fine.

"In nature, acids come in a variety of strengths; acid spells, however, assume a uniform potency of acid."

And the corrosive maximum would be 17.5 at maximum, the rest is toxic damage. However, I will drop it to 1 cor damage point if that makes it feel better.

This would be the result:
Follow-up [1d-1 tox 1 cor terrible pain; secondary choking] (HT-2 to resist) every 10 seconds for 1 minute

I would also like you to consider that the ants are not 1 cm long, they´re almost 50 cm long, with a head length of about 13 cm and appropriate mandibular glands (***). So following your math (and assumming it was right) it´s actually 4.8 meters per second (I include a corrected calculation at the end of my post).

Put the mandibular glands down to about 30 secretory cells of around 3.75mm each for shorter mandibles (although I like them long and scary). That would be a bit over 6.66 meters per second.

Possible design
Design

Corrected calculation:
And if you want to stay true to the original design of a single sting make it 6.25 mm diameter, for a surface of over 30 sq mm, making it 120m/s (12.2kg-m/s), which considering that they can lift 80kg with a x-heavy load, should not be much at a recoil speed of 6m/s if the ants weigh 15kg or 12m/s if we lower them to weigh 7.5kg. And even then we need to remember that the lethal dose is 18.75g for a 125 lbs person, not 750g.

For comparison:
Muzzle velocity is the speed of a projectile at the moment it leaves the muzzle of a gun. Muzzle velocities range from approximately 120 m/s (390 ft/s) to 370 m/s (1,200 ft/s) in black powder muskets, to more than 1,200 m/s (3,900 ft/s) in modern rifles with high-performance cartridges such as the .220 Swift and .204 Ruger.

[Alonsua]

By the way Formic acid has a pka of 3.75 Acetic acid has a pka of 4.75. Therefore formic acid is a stronger acid than acetic acid.

From acetic acid we got the following: "being splashed with it causes 1 point of corrosion damage; being immersed in it, 1d-3 corrosion damage per second; and swallowing it, 1d+1 corrosion damage at the rate of 1 HP per 15 minutes.".

From basic campaign we have the following too: "If the victim is immersed in acid, he takes 1d-1 corrosion damage per second." and "If the victim swallows acid, he takes 3d damage at the rate of 1 HP per 15 minutes. A successful Physician or Poisons roll can halt this damage; treatment requires 2d minutes.".

Since what these ants do is not to spit it, but to inject it, I think it should have an effect similar to having swallowed it. What does "at the rate of 1 HP per 15 minutes" stand for? Permanent HP damage?

[whswhs]

Originally Posted by Alonsua

By the way Formic acid has a pka of 3.75 Acetic acid has a pka of 4.75. Therefore formic acid is a stronger acid than acetic acid. And about Acetic Acid we got the following: "being splashed with it causes 1 point of corrosion damage; being immersed in it, 1d-3 corrosion damage per second; and swallowing it, 1d+1 corrosion damage at the rate of 1 HP per 15 minutes.".

Is that for pure acetic acid?

Do ants secrete pure formic acid, or formic acid in aqueous solution? If the latter, what's the concentration?

[Alonsua]

Originally Posted by whswhs

Is that for pure acetic acid?

Do ants secrete pure formic acid, or formic acid in aqueous solution? If the latter, what's the concentration?

Let´s clear what does "he takes 3d damage at the rate of 1 HP per 15 minutes" stand for first XD

*Do it "concentrated" formic acid (80%).
*Acetic acid is at TL0, appears on the low-tech book and only states "concentrated".

[mr beer]

Originally Posted by AlexanderHowl

It is also impossible to deliver such an attack directly into the blood stream (if you assume 750 grams). The poison glands would likely have a crosssection of 1 mm, which would mean that they would need to deliver the acid at 750 meters per second to deliver all of the acid in one bite to the blood stream. With that much force, the recoil would blow the head of the ant off at 150 meters per second.

See now we have giant ants that have a water jet cutting attack, except they use acid instead of water. Now that's scary.

[Alonsua]

Originally Posted by mr beer

See now we have giant ants that have a water jet cutting attack, except they use acid instead of water. Now that's scary.

Although the sting is impaling, only the mandibles are cutting.

And quoting:

Corrected calculation:
And if you want to stay true to the original design of a single sting make it 6.25 mm diameter, for a surface of over 30 sq mm, making it 120m/s (12.2kg-m/s), which considering that they can lift 80kg with a x-heavy load, should not be much at a recoil speed of 6m/s if the ants weigh 15kg or 12m/s if we lower them to weigh 7.5kg. And even then we need to remember that the lethal dose is 18.75g for a 125 lbs person, not 750g.

For comparison:
Muzzle velocity is the speed of a projectile at the moment it leaves the muzzle of a gun. Muzzle velocities range from approximately 120 m/s (390 ft/s) to 370 m/s (1,200 ft/s) in black powder muskets, to more than 1,200 m/s (3,900 ft/s) in modern rifles with high-performance cartridges such as the .220 Swift and .204 Ruger.