Armor as DR dice

[DanMcS]

I would like to use armor as DR, but using the straight armor values seems too high (a breastplate could never be penetrated by a dagger). I was perusing my old Alternity books the other night, and received inspiration. In Alternity, armor provided DR, but it was a die value.

If you convert the armor bonuses of regular armor to die values, you get something like this:

[color=white]
Armor        DR  Average Result
Padded       d1     1
Leather      d2    1.5
Studded      d3     2
Chain Shirt  d4    2.5
Hide         d3     2
Scale        d4    2.5
Chain        d5     3
Breastplate  d5    3
Splint        d6    3.5
Banded       d6    3.5
Halfplate    d7     4
Fullplate    d8     4.5
[/color]

This can be tweaked if you like, for instance, you might drop all the heavy armors two die sizes (d8 to d6, d7 to d5, etc) and add 1, which gives the same average but a smaller range. Less randomness tends to be better for PCs.

Enhancement bonuses on armor add to this directly, so Full Plate +2 gives DR d8+2/-.

If you make shields still provide AC bonuses, you're set. This tends to make Armor of Invulnerability less valuable, but that's one item out of many, and it's not completely useless, since it provides set DR instead of variable. Maybe reduce the price of it to +2 equivalent. So Banded Mail +1 of Invulnerability would provide DR 5/magic and d6+1/-, use whichever helps more on that hit.

As the DM, then you can assume average values for all your NPCs if it helps you speed things back up. It shouldn't be too bad, since the attack dice and the DR dice are rolled by different people, and can be done simultaneously.

 

[Spatzimaus]

It's not a bad idea, but it suffers from the same problem all Armor-as-DR systems have: the very weapons most often used in Real Life to defeat heavy armor are the ones most hurt by a DR system.

You also run into the problem that DR d8/- just isn't that much. It's useful at low levels, sure, but against a 20th-level Power Attacking guy with a greatsword, it's not even a speedbump.
A 3.5E Power Attacker trades 1 point of attack bonus for 1-2 damage (2 for 2-handed weapons). By replacing the +8 AC for full plate with d8/- DR, I allow the enemy to Power Attack for 8 more than he would have, doing 16 extra damage. So, unless my DR stops 16 points of damage per attack, it won't break even against those enemies.
Even if you stay with the 1:1 ratio of 3E, you'd still need it to give DR 8/- just like the usual suggestions. Or, give DR 2d8/-. Better yet, you could do it half-and-half, like this:
Padded: +0 AC, 1d2 DR
Leather: +1 AC, 1d2 DR
Studded: +1 AC, 1d4 DR
Chain Shirt: +1 AC, 1d6 DR
Hide: +2 AC, 1d4 DR
Scale: +2 AC, 1d6 DR
Chain: +3 AC, 1d6 DR
Breastplate: +2 AC, 1d8 DR
Splint: +3 AC, 1d8 DR
Banded: +2 AC, 1d10 DR
Half-Plate: +3 AC, 1d10 DR
Full Plate: +4 AC, 1d10 DR
The logic here was, a mix-and-match armor like BP or Chain Shirt would have the AC of the lower type and the DR randomness of the higher type. I also stuck to using standard dice sizes (except d2, of course, but flipping a coin isn't too tough). It also makes Max DEX bonus a bit more complex.

What we did IMC instead was make a hybrid AC/DR system based on exotic materials:
1> Armors still add the full amount to AC, as normal.
2> Heavier armors also give a Material-based DR, based on the Hardness of the material used to make them. Medium armors and Large shields give DR (Hardness/10)/-, Heavy armors give DR (Hardness/5)/-. Note that steel has Hardness 10, so that'd be DR 1/- for a breastplate or 2/- for full plate.
3> The material used in the weapon can help offset this a bit; for most materials they penetrate (Hardness/10) of material DR automatically. Certain types of weapons penetrate (Hardness/5), including longbows, heavy crossbows, lances while mounted, or certain exotic weapons (including a couple exotic daggers we added).

This also helps a bit with animals; if you know the hardness of Dragonhide, you can have dragons trade some of that Natural Armor for a material-based DR.

 

[the Jester]

Hmm, interesting system.

I personally think armor's fine as-is, but your idea is prolly the best of the armor-as-DR systems I've seen.

 

[DanMcS]

I like it in concept, but Spatz is right, if the average DR isn't roughly equivalent to the old Armor bonus, there is a big swing towards Power Attack. The statistical fix is to either double the DR dice (numerically or literally, ie 1d8 could become 1d16 or 2d8, you get the same result within .5 hp), or leave the DR dice the same and have the armor provide half its old armor bonus to AC, like he suggests.

I'm not horrendously concerned about the two-handed power attack thing, since many of those are weapons which were designed to crack into armor, ie the greatsword, etc. So if they accomplish that in-game, I'm fine with that, but it is something to keep in mind.

Power Attack should provide 1.5/1 damage for two-handed weapons, anyway.