Defense Scaling

[Aroooo]

Can someone refresh my memory (it is Friday after all)? As I understand it, each increase in damage class is supposed to represent a doubling of effective output, yes? If so, how are defenses scaled (for lack of a better term) up. How many points of defense represent a doubling of the previous 'level' of def?

 

Aroooo

[Tom McCarthy]

I think 1 DEF is supposed to represent roughly doubling the defence of an object, or for characters, between 1.5 and 2.5 PD or ED depending on the campaign. In my campaign, characters typically have 2 PD or ED for each DC of a typical attack, with martial artists having more like 1.5 and bricks more like 2.5. By the time the typical attack goes up 2 DC, expect people to go up about 4 PD and ED.

[Bartman]

I couldn't find a reference for DEF but +2 Body equals a doubling of a non-living item's mass.

[nuada]

I couldn't find a reference for DEF but +2 Body equals a doubling of a non-living item's mass.

 

It's a good thing this isn't true for heroes! My character would weigh about 368,640 pounds. Sheesh! No one would /ever/ teleport him around.

 

Anyway, as to the (interesting) topic at hand, I don't know that defense has the same logarithmic scale as DC's. If you look at the defensive values of things like stone vs. steel vs. reinforced concrete, etc., there's no logical 'doubling' going on. That is to say, a 12 def, 10 body wall is not twice as strong as a 10 def, 10 body wall, despite the fact that an additional damage class would be required to affect it, on average.

 

The doubling of power of DC's never really seemed to be all that universal to me. Just look at any of the threads about nuclear blasts vs. tank guns/armor and you'll see what I mean. The game numbers don't really scale to real world effects quite as neatly as the FREd would have us believe. In my opinion, anyway.

 

[edited for subject/berb agreement]

[Arthur]

The closest thing to a real-world correlation was in the Fantasy Hero armor rules. Every doubling of mass gave +2 DEF. Doubling of mass is not a perfect model for "twice as protective in real life", but it's as close as I ever saw.

 

Therefore, I would say +2 DEF represents a doubling of effectiveness.

 

This also makes sense based on points. +5 STR or +1 DC represents a doubling of energy (at least until FRED) for 5 AP.

 

Armor 2/2 as a power costs 6 AP - as close as you're going to get to match DEF to points.

[nuada]

right but if I recall correctly (and I probably don't, but I don't have my book with me), stone has a defense of 6 and concrete has a defense of 8. Yet, concrete is definitely not twice as tough as stone (especially depending on the stone, but assuming something generic like granite, this is patently untrue).

 

The real-world correlations to defensive properties of objects just don't scale exponentially.

 

Let's look at Mo's scale of hardness (dusting off the geology class notes from 15-ish years ago, so bear with me), where a finger nail is roughly 2.5 in hardness and quartz has a hardness of 7 and diamond has a hardness of 10. It is reasonable to say that a fingernail is only 1/4th as hard as a diamond, based on this scale. Similarly, a piece of quartz is 2 and a half times harder than a fingernail.

 

Now, I would be hard pressed to assign a defensive value to a fingernail. Diamond, on the other hand, probably has a defense of something like 12 or 14. Please feel free to disagree with me if you like.

 

However, if we assume a wall of diamond has a defense of 12, then a wall of fingernails (ewww) should have a defense of 8, by your math (where 2 defense is equal to double the hardness). Hopefully, the ridiculousness of a PD 8 fingernail is obvious.

 

I would say that, as long as you're not trying to bring this into real-world examples, you're fine going with the 5 points to buy 1 DC is countered by 6 points to buy 2 def and 2 body. But if you're looking for the game's logical doubling point for hardness in real-world objects, I don't think you're going to find it.