Quick Question: LAW

[buzz]

Well I don't think it's unreasonable to expect that they be crossover-compatible?

It's a little unreasonable, IMHO, as one is a high fantasy/near-mythic game with abundant magic, and the other modern-day action that features, at best, 5th-level magic in those campaign models that even allow such things. If the authors had not made any accomodations for the difference in intended genres, I think we'd be arguing about a lot more than just how much damage a LAW does.

My beef isn't with the area-effect damage from the LAW, which sounds fine, it's the fact that you can't do significantly more damage with a _direct hit_ that's silly.

I suppose. I don't think that it really matters all that much, though. The average MDT of even a 20th-level hero isn't going to be far above the *absolute minimum* damage the LAW will do (10hp) if they miss the Reflex save. Ergo, any ordinaires or low-level heroes are essentially dead or dying automatically on a "direct hit." Heroes of higher level have a better chance, but, well, that's why they're high-level. E.g., James Bond gets shot at with all kinds of high-power weaponry and he never dies.

(I'd also think that a LAW wold probably punch right through you and then detonate at some point behind you once it hit something more substantial, thereby doing roughly the same damage listed... but I'm no weapons expert.)

If that's not lethal enough for you, find an RPG that is. You can probably pick up a copy of Phoenix Command for cheap on eBay.

 

[S'mon]

(I'd also think that a LAW wold probably punch right through you and then detonate at some point behind you once it hit something more substantial, thereby doing roughly the same damage listed... but I'm no weapons expert.)

If that's not lethal enough for you, find an RPG that is. You can probably pick up a copy of Phoenix Command for cheap on eBay.

You're probably right about it punching through - leaving a a hole several inches across; the kinetic impact and tissue damage would be fatal if it hit your torso.

I don't have Phoenix Command; for my deity-level AD&D PCs vs Arasaka Corporation games on Cyberpunk Earth 2020 I used Twilight:2000 for the bigger weapons - in T2000 a 9mm pistol does 1d6 damage, a .44 Magnum does 2d6... an RPG-7 does 55d6, and a LAW does 110d6 AIR. At one point when the Araska Power-Armour ACPA troopers were attacking Gladsheim, Thrin (Upper_Krust's deity PC) took over 500 damage in one round from an automatic 40mm grenade launcher (he had 798hp max); but he was most afraid of assault shotguns (9d6 dmg/hit), several Solo mercs with shotguns was what took him down when he walked into an ambush on Earth and got dispelled back to Asgard.

Obviously 3e can't be used for this - 3e Deities & Demigods deities will trash any number of 50 hit point MBTs, while their cannons do, what, 10d6 dmg to deities with thousands of hp?

 

[S'mon]

Well, you don't flavor-text it as a direct hit, then, do you?

I think that (that a LAW never actually directly hits anyone) is ok for PCs and other human-sized creatures - I'd expect it's practically impossible to hit a moving human with a LAW, if they were aware they were being fired at. But what happens when the dragons attack? Having LAWS impacting on the flanks of the red dragon for 10d6 damage when the dragon has 600 hp and a Fort save over +20 is just going to tickle it.

With monsters and mechanics existing on totally different damage scales, it becomes impossible to run anything like a 'Reign of Fire' type campaign, with humans using heavy weaponry vs big monsters. Even a hill giant can take severa LAW hits on these figures.

 

[Upper_Krust]

Hi all!

There are a number of problems with converting modern weaponry over to 3.5 (or d20 Modern for that matter).

One is that the scaling system for damage since 3rd Edition has been warped.

Think about it; a Colossal Dragons bite only deals the same base damage as two greatswords. Surely a 100 Ton dragons claw attack is going to hit you like a 18 wheel juggernaut doing 60 mph!?

Not according to the official rules.

Obviously thats why the Kurgan was happy to play chicken on the motorway - he was only going to take 4d6 damage in the crash anyway!

If we look a bit deeper into the mechanics we see that:

Each Size category increase = (roughly) x2 HD = x8 mass = x1.5 base damage

That constant gives a ridiculous skew of mass to damage but it is consistent between Hit points and Damage (x2 HD = x1.5 damage).

So if we assume that each size increase multiplies the energy of the attack by x4 (x8 mass but roughly three quarter velocity) to get an increase of x1.5 damage.

Then once we work out the base damage for a pistol (eg. 2d6) then we simply double the damage for the average increase that provides x8 energy.

So you can have a rough table as follows:

Kinetic Damage

Pistol: 2d6
Rifle (5.56mm): 4d6
Sniper Rifle (12.7mm): 8d6
25mm Cannon: 16d6
50mm Cannon: 32d6
100mm Cannon (Main Battle Tank): 64d6
200mm Guns (Howitzer): 128d6
400mm Guns (Battleship): 256d6

This of course only counts the kinetic energy for a direct hit, not any subsequent blast damage.

However the principle remains the same; increasing the effective TNT yield by a factor of x8 increases the damage by a factor of x2.

The tricky part however is accurately finding out the explosive yield of some weapons and balancing that with kinetic energy.

My best guess is that a typical 40mm hand grenade (125g) will deal 16d6 damage to a 5m radius.

So 1 kg rocket (explosion) will deal 32d6 to a 10 m radius

A 8 kg rocket (explosion) will deal 64d6 in a 20m radius

A 64 kg Missile (explosion) will deal 128d6 to a 40 m radius. (eg. Hellfire)

A 512 kg Missile (explosion) will deal 256d6 to an 80m radius. (eg. Patriot)

etc.

In my opinion the kinetic energy of a rocket is generally equal to its explosive yield. While the explosive energy of tank shells or larger munitions is about equal to half the kinetic damage.

So a LAW (4kg) will deal 48d6 kinetic damage and 48d6 blast damage (48d6: average 336)

Whereas a 100mm Tank shell would deal 64d6 kinetic damage and 32d6 blast damage (96d6: average 336)

Then of course you have to account for Armour Protection etc.

The above stats suggest a Main Battle Tank has Damage Reduction in the order of 512. Thats probably about 128 per inch of Chobham armour, which is itself four times stronger than steel so one inch of steel plate probably gives about 32 points of protection.

Primary (special steel used was about double the tensile strength of ordinary steel) Battleship Armour is about one foot thick (suggesting about DR/768) at the strongest points (such as gun turrets).

 

[S'mon]

Thanks U_K - what I like about this realistic approach is that it actually supports the introduction of fantasy elements much better than the usual "handwave" approach to mechanical damage. When dragons and heavy weapons are on the same scale, you can run fights featuring both. On the d20 stats given above, a LAW would be barely enough to kill a regular heavy warhorse!

 

[Upper_Krust]

Hi S'mon!

Thanks U_K - what I like about this realistic approach is that it actually supports the introduction of fantasy elements much better than the usual "handwave" approach to mechanical damage. When dragons and heavy weapons are on the same scale, you can run fights featuring both. On the d20 stats given above, a LAW would be barely enough to kill a regular heavy warhorse!

I meant to add that if you determine the pistol damage to be 1d6 (instead of the 2d6 listed above) then you halve all the above stats.

If Base Pistol Damage is 1d6 then use the following:

Pistol: 1d6
Rifle (5.56mm): 2d6
Sniper Rifle (12.7mm): 4d6
25mm Cannon: 8d6
50mm Cannon: 16d6
100mm Cannon (Main Battle Tank): 32d6 (kinetic) + 16d6 (explosive)
200mm Guns (Howitzer): 64d6 (kinetic) + 32d6 (explosive)
400mm Guns (Battleship): 128d6 (kinetic) + 64d6 (explosive)

125g Grenade: 8d6 (explosive)
1kg Rocket: 16d6 (explosive) + 16d6 (kinetic, direct hit)
8kg Rocket: 32d6 (explosive) + 32d6 (kinetic, direct hit)
64kg Missile: 64d6 (explosive) + 64d6 (kinetic, direct hit)
512kg Missile: 128d6 (explosive) + 128d6 (kinetic, direct hit)
4 Ton Missile: 256d6 (explosive) + 256d6 (kinetic, direct hit)

1 inch of Steel = DR/16
1 inch of Homogenous Steel (superior WW2 Armour) = DR/32
1 inch of Chobham (superior Modern Armour) = DR/64

If the base Pistol damage is 2d6 then obviously double all the above...I think I can guess which you'll be using S'mon.

 

[Upper_Krust]

Hi All!

Just a small addition to my previous post.

Under the d20 Modern firearms rules (which appear to scale about half as fast as they should*) a 128 Kiloton Nuclear device would deal 192d6 (averaging 672 damage). Meaning that (BoVD) Orcus could survive a nuke in the face.

It also appears that a Human could smoke dynamite (for those Wile E Coyote moments).

*If you were creating realistic parallels between the d20 system and reality.

d20 Modern seems more like a (low physical factor) comic book representation of the modern world rather than the brutal reality presented in the weapon stats I outlined previously.

By the way S'mon, I honestly think that starting Pistol damage at 1d6 is the better option for two reasons.

Firstly, I don't see Uzi rounds dealing more damage than Arrows.

Secondly, using the 1d6 Pistol as a starting point seems to suggest that Steel has a hardness of about 15 which is plausible. Whereas using 2d6 suggests Steel has a hardness of 30 which seems implausible.

Any thoughts?

 

[takyris]

* considers ranting about abstract combat system and one could make the same argument for daggers (ie, "Only 1d4? So an ordinary guy could stab himself in the throat with a dagger and survive?")
* gives up

If that works for you, fire away. Best of luck to you.

 

[DMScott]

d20 Modern seems more like a (low physical factor) comic book representation of the modern world rather than the brutal reality presented in the weapon stats I outlined previously.

Indeed - that's why on the back of the book they talk about action movies and first person shooters. A sufficiently interested person could probably come up with a good high realism modern day d20 game, but I have a feeling it'd be better to start from scratch rather than work from d20 Modern's starting point. Or perhaps Spycraft can do it - I haven't read that one, but it seems a bit grittier from reviews and such.

In standard d20 Modern, I think really heavy weapons are probably better handled via save-or-die (or just die) mechanics than rolling great handfuls of dice.

 

[buzz]

FWIW, if you really want to heighten the lethality in d20M, dial the MDT down to a flat 10 for normal folks, and maybe Con or higher for monsters, and then use the Scaling the Saving Throw variant for massive Damage from UA.

Or just grab a copy of GURPS or HERO.