Armor-granted DR - w/o complications or balance issues

[nonsi]

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Armors grant DR to some degree, provided that the wearer is aware of the incoming attack and may properly defend themselves.
If you're flatfooted, flanked, or lose your Dex-bonus to AC for any reason, you don't benefit from armor-associated DR.


All armors grant DR 1/― from the get go.
Some armors may grant higher DR, depending on the specific armor. See the "Damage Reduction" column in the first table here.
To gain DR 2/― from armor, you must have at least BAB +4.
To gain DR 3/― from armor, you must have at least BAB +8.
To gain DR 4/― from armor, you must have at least BAB +12.

Spoiler: Armor-Associated DR

Show

With level progression, characters learn to make more out of their armor – in the form of DR.

For armors with which the character is proficient, at BAB +2 ... +8, each +2 armor-bonus to AC (not including magical bonuses) grants DR 1/―, capped by ½ the character’s BAB.
Examples:
1. DR 1/― from Leather (or better) armor, starting at BAB +2
2. DR 2/― from Chain Shirt (or better) armor, starting at BAB +4
3. DR 3/― from Banded Mail (or better) armor, starting at BAB +6
4. DR 4/― from Full Plate armor, starting at BAB +8

Starting at BAB +10 and every +2 increase thereafter, the DR increases by 1 for any armor you’re proficient with. This does not progress beyond BAB +20.

Armor-associated DR stacks with any other DR.

Armor-associated DR is gained from experience only. It doesn’t apply to monster HD / racial HD. Only BAB gained by actual level progression counts.


This makes Leather armor end up with DR 7/― and Full Plate end up with DR 10/―.
Breastplate would grant a level 20 Barbarian an accumulated DR 13/―.

Clarification: The idea is to add DR on top of AC, not to replace armor-bonus to AC.

Design Note: the idea is to scale DR with the armor types, but to avoid making things broken at low levels. At mid-levels, the party tank and the healer will enjoy decent lastability.

[Nifft]

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Not sure this helps much.

The values seem a bit low.

[nonsi]

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Not sure this helps much.

The values seem a bit low.

Guess I could lower the BAB requirements to +4/+7/+10, or +3/+6/+9, but I'm not sure about it.
W/o lowering armor ACs, DR 3/― and up is definitely broken at 1st level.
Also, the Barb gets DR 1/― at 7th level and DR 4/― at 16th, and I see no reason why both factors of DR shouldn't stack.

[Maat Mons]

You know theoretically, each point of AC is supposed to decrease your chances of being hit by 5%. And, on average, being hit by attacks 5% less often means you take 5% less damage in the long run.

So, in a sense, we can say that the intention is for the protection of a suit of full plate to be on par with 40% DR. That means, if we want to know how much flat damage reduction a suit of full plate should offer to a 20th-level character, we just have to ask ourselves "What's 40% of the average damage a 20th-level character takes per hit?"

[nonsi]

You know theoretically, each point of AC is supposed to decrease your chances of being hit by 5%. And, on average, being hit by attacks 5% less often means you take 5% less damage in the long run.

So, in a sense, we can say that the intention is for the protection of a suit of full plate to be on par with 40% DR. That means, if we want to know how much flat damage reduction a suit of full plate should offer to a 20th-level character, we just have to ask ourselves "What's 40% of the average damage a 20th-level character takes per hit?"

It doesn't seem right to me to allow a 1500gp worth of mundane equipment to deny 40% of the average damage that a 20th level frontliner is expected to take/negate overall.
+9 to AC and +4 DR seem more than reasonable for a single mundane item to me.

My only dilemma is the correct pace at which armor-associated DR should be available.
By the responses so far, it seems that I'm pulling upward toward 12 while you two are pulling downward. Just how much downward is unclear to me.
Now that I think of it, maybe certain feats could up armor-associated DR somewhat.

[Knaight]

It doesn't seem right to me to allow a 1500gp worth of mundane equipment to deny 40% of the average damage that a 20th level frontliner is expected to take/negate overall.
+9 to AC and +4 DR seem more than reasonable for a single mundane item to me.

It doesn't do that. It negates 40% of the average damage that comes through attack rolls (approximately, there's enough that falls/rises off/over the scale to throw it off a bit). Anything resisted with a save bypasses it entirely. That's what the +8 AC does on its own, so if you replace AC with DR you'd want something similar.

EDIT: More precisely, 40% of the time it negates damage that comes through attack rolls. Unless they attack rolls generally hit 100% of the time that actually negates more than 40% of incoming damage, to a theoretical maximum of 88.9% damage reduction for attacks that hit on an 11 when unarmored. I'd repeated phrasing used in the thread, but said phrasing is sloppy, and it's only not edited to be better because it's been quoted.

[nonsi]

It doesn't do that. It negates 40% of the average damage that comes through attack rolls (approximately, there's enough that falls/rises off/over the scale to throw it off a bit). Anything resisted with a save bypasses it entirely. That's what the +8 AC does on its own, so if you replace AC with DR you'd want something similar.

Oh, now I get the problem.
I was talking about adding DR on top of AC, not instead.

[Knaight]

You know theoretically, each point of AC is supposed to decrease your chances of being hit by 5%. And, on average, being hit by attacks 5% less often means you take 5% less damage in the long run.

Not quite. Going from getting hit 100% of the time to 95% of the time corresponds to 5% less damage in the long term. On the other extreme going from getting hit 10% of the time to getting hit 5% of the time corresponds to 50% less damage in the long term (counting only AC intercepted damage sources). In practice it ends up somewhere between those numbers, and each point of AC does a different amount, with subsequent points adding more than prior points up until you force the auto-20 hit rules, at which point it does nothing.

For n points of AC the expected reduction is (5n/h)%, where h is the earlier hit chance, assuming that you're not running into automatic hit and miss rules.

Oh, now I get the problem.
I was talking about adding DR on top of AC, not instead.

That still works out to an increase of more than 40% from a mundane item, here 45+% to start with, before DR is taken into account. Which still only applies to damage from non-touch attacks.

[nonsi]

Not quite. Going from getting hit 100% of the time to 95% of the time corresponds to 5% less damage in the long term. On the other extreme going from getting hit 10% of the time to getting hit 5% of the time corresponds to 50% less damage in the long term (counting only AC intercepted damage sources). In practice it ends up somewhere between those numbers, and each point of AC does a different amount, with subsequent points adding more than prior points up until you force the auto-20 hit rules, at which point it does nothing.

For n points of AC the expected reduction is (5n/h)%, where h is the earlier hit chance, assuming that you're not running into automatic hit and miss rules.


That still works out to an increase of more than 40% from a mundane item, here 45+% to start with, before DR is taken into account. Which still only applies to damage from non-touch attacks.

I still can't put my finger on your conclusion regarding my proposal in the OP.

[Glimbur]

What kind of attacks that are affected by DR are mid level characters being targeted with? A CR 11 cloud giant is rocking 4d6+18 damage per swing, which makes 4 DR feel pretty insignificant. It's an interesting idea but I think it needs to scale faster.

[nonsi]

What kind of attacks that are affected by DR are mid level characters being targeted with? A CR 11 cloud giant is rocking 4d6+18 damage per swing, which makes 4 DR feel pretty insignificant. It's an interesting idea but I think it needs to scale faster.

ATM, it's an added bonus that doesn't cost any additional character resources. Nevertheless, when you say "faster", what do you have in mind?

[XionUnborn01]

ATM, it's an added bonus that doesn't cost any additional character resources. Nevertheless, when you say "faster", what do you have in mind?

The problem is that, at 20th level or at 12th even, 4 DR is basically nothing. Maybe it increases at 2bab, 5, 8, 11, 14, 17, 20 that way its 8dr at 20th. Still not amazing but might actually make a difference.

[nonsi]

The problem is that, at 20th level or at 12th even, 4 DR is basically nothing. Maybe it increases at 2bab, 5, 8, 11, 14, 17, 20 that way its 8dr at 20th. Still not amazing but might actually make a difference.

1. Your suggested progression still spells out 4 DR at BAB +12.
2. How do I reconcile the different armor types with your proposed progression?

[Erloas]

I would scale DR based on the AC, and then scale it up every 4 levels.

Starting point: AC/3 (normal rounding) gives DR
So:
AC 1 armor = 0 DR

AC 2, 3, 4 armor = 1 DR

AC 5, 6, 7 armor = 2 DR
AC 8, 9 armor = 3 DR

At level 4 those x2:, so 0, 2, 4, 6
level 8, x3 = 0, 3, 6, 9
level 12, x4 = 0, 4, 8, 12
level 16, x5 = 0, 5, 10, 15
level 20, x6 = 0, 6, 12, 18

That seems like a reasonable starting off point. If you wanted that to increase with magic bonuses or not would be a matter of balance to be determined. By having the DR scale to the armor you're not getting the same DR in cloth as you are in full plate. Depending how those numbers feel, you could instead round down (so 1, 2=0, 3, 4, 5 =1, etc) or you could round up. If you wanted a larger spread, divide by 2 instead, a smaller spread, divide by 4. Less progression then change it after 5-6 levels instead of 4.

If you wanted it more restrictive you could add it to something like Armor Focus feat for 1-8, Improved Armor Focus for 12-20, something a martial class would be likely to do anyway.

[Maat Mons]

On the other extreme going from getting hit 10% of the time to getting hit 5% of the time corresponds to 50% less damage in the long term (counting only AC intercepted damage sources).

10% versus 5% is a 5 percentage point difference. I'm sorry if my phrasing was ambiguous. I figured saying "percentage point" would confuse anyone who wasn't familiar with statistics.

Oh, now I get the problem.
I was talking about adding DR on top of AC, not instead.

Now, my experience with high-level play is limited. But my understanding is that, since attack bonus increases with level/CR more rapidly than AC, the value of an armor's AC bonus diminishes with level.

So, at 1st level, a suit of armor makes a big difference in average damage taken. Conversely, at high level, wearing armor takes you from being hit on anything but a natural 1 to ... still being hit on anything but a natural 1.

If we figure that the armor's AC bonus is, after a point useless, then, after that point, it really doesn't matter if the new benefit is on top of it or instead of it.

Design Note: the idea is to scale DR with the armor types, but to avoid making things broken at low levels.

Why does there need to be any DR at 1st level? Isn't the AC bonus from armor a pretty substantial benefit at that level?

It doesn't seem right to me to allow a 1500gp worth of mundane equipment to deny 40% of the average damage that a 20th level frontliner is expected to take/negate overall.
+9 to AC and +4 DR seem more than reasonable for a single mundane item to me.

ATM, it's an added bonus that doesn't cost any additional character resources.

Putting 20 levels into a martial class is an investment. Creating a system whereby the people who have made that investment use armor more effectively is not the same as making the armor itself more powerful. A 20th-level character can use a free quarterstaff more effectively than a 1st-level character can. The quarterstaff itself is not is not overpowered because of this.

[mabriss lethe]

OK. Here's a thought. Don't worry about DR and AC stacking at all, or whether or not it's level dependent. Just keep it as part of the equipment. If you feel like it's too powerful, just make sure that DR from conventional armor can be overcome by one of the three basic weapon damage types, then go nuts. Chain shirt would still retain its AC bonus no matter what, but would be overcome by a piercing weapon. Plate would be vulnerable to Bludgeoning, Hide to Slashing (or whatever you ultimately decide, those are just arbitrary, off the cuff choices). Magic enhancement could change it to X/-, but I'm not sure exactly how I'd do that at the moment, it's easy for that to get too fiddly.

[Erloas]

So here is an updated set of versions. All the options end up more powerful than the original, but I think it gives a reasonable progression. I decided to skip level 1-3, going with AC being a big enough boost as it is then. I also went ahead and expanded it to AC 14, in case you wanted to include the enchantment bonus, so +5 full plate would be the 14 row. (not that a level 4 is going to be running around in +5 full plate, but whatever) If not, just ignore that and the table stops at AC 9. Seems like a lot all at once, but once you pick a method 3/4 of the table goes away. If you wanted to start it at a different level and progress less just drop the 16-20 column and readjust the level spread.

The formula is pretty straight forward, AC/3 or AC/4, just rounded differently and then multiplied as level increases.

Spoiler: sample DR tables

Show

AC	Large Spread, round normal				Large Spread, round down				Small Spread, round normal				Small Spread, round down
Level	4-7	8-11	12-15	16-20	4-7	8-11	12-15	16-20	4-7	8-11	12-15	16-20	4-7	8-11	12-15	16-20
multiplier	x1	x2	x3	x4	x1	x2	x3	x4	x1	x2	x3	x4	x1	x2	x3	x4
1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
2	1	2	3	4	0	0	0	0	1	2	3	4	0	0	0	0
3	1	2	3	4	1	2	3	4	1	2	3	4	0	0	0	0
4	1	2	3	4	1	2	3	4	1	2	3	4	1	2	3	4
5	2	4	6	8	1	2	3	4	1	2	3	4	1	2	3	4
6	2	4	6	8	2	4	6	8	2	4	6	8	1	2	3	4
7	2	4	6	8	2	4	6	8	2	4	6	8	1	2	3	4
8	3	6	9	12	2	4	6	8	2	4	6	8	2	4	6	8
9	3	6	9	12	3	6	9	12	2	4	6	8	2	4	6	8
10	3	6	9	12	3	6	9	12	3	6	9	12	2	4	6	8
11	4	8	12	16	3	6	9	12	3	6	9	12	2	4	6	8
12	4	8	12	16	4	8	12	16	3	6	9	12	3	6	9	12
13	4	8	12	16	4	8	12	16	3	6	9	12	3	6	9	12
14	5	10	15	20	4	8	12	16	4	8	12	16	3	6	9	12

[nonsi]

Now, my experience with high-level play is limited. But my understanding is that, since attack bonus increases with level/CR more rapidly than AC, the value of an armor's AC bonus diminishes with level.
So, at 1st level, a suit of armor makes a big difference in average damage taken. Conversely, at high level, wearing armor takes you from being hit on anything but a natural 1 to ... still being hit on anything but a natural 1.
If we figure that the armor's AC bonus is, after a point useless, then, after that point, it really doesn't matter if the new benefit is on top of it or instead of it.

There are AC factors other than just the armor:
1. Mithral - improves Dex benefits.
2. Magical bonuses.
3. Feats
4. Buff spells and effects.
5. Circumstance bonuses.
6. Battle strategy and tactics.

Yes. There comes a time when all those can't keep up, but that usually happens at epic levels.

Why does there need to be any DR at 1st level? Isn't the AC bonus from armor a pretty substantial benefit at that level?

I'll make it BAB +1 rather than level 1.

Putting 20 levels into a martial class is an investment. Creating a system whereby the people who have made that investment use armor more effectively is not the same as making the armor itself more powerful. A 20th-level character can use a free quarterstaff more effectively than a 1st-level character can. The quarterstaff itself is not is not overpowered because of this.

We see things eye to eye on this one.

[nonsi]

So here is an updated set of versions. All the options end up more powerful than the original, but I think it gives a reasonable progression. I decided to skip level 1-3, going with AC being a big enough boost as it is then. I also went ahead and expanded it to AC 14, in case you wanted to include the enchantment bonus, so +5 full plate would be the 14 row. (not that a level 4 is going to be running around in +5 full plate, but whatever) If not, just ignore that and the table stops at AC 9. Seems like a lot all at once, but once you pick a method 3/4 of the table goes away. If you wanted to start it at a different level and progress less just drop the 16-20 column and readjust the level spread.

The formula is pretty straight forward, AC/3 or AC/4, just rounded differently and then multiplied as level increases.

Spoiler: sample DR tables

Show

AC	Large Spread, round normal				Large Spread, round down				Small Spread, round normal				Small Spread, round down
Level	4-7	8-11	12-15	16-20	4-7	8-11	12-15	16-20	4-7	8-11	12-15	16-20	4-7	8-11	12-15	16-20
multiplier	x1	x2	x3	x4	x1	x2	x3	x4	x1	x2	x3	x4	x1	x2	x3	x4
1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
2	1	2	3	4	0	0	0	0	1	2	3	4	0	0	0	0
3	1	2	3	4	1	2	3	4	1	2	3	4	0	0	0	0
4	1	2	3	4	1	2	3	4	1	2	3	4	1	2	3	4
5	2	4	6	8	1	2	3	4	1	2	3	4	1	2	3	4
6	2	4	6	8	2	4	6	8	2	4	6	8	1	2	3	4
7	2	4	6	8	2	4	6	8	2	4	6	8	1	2	3	4
8	3	6	9	12	2	4	6	8	2	4	6	8	2	4	6	8
9	3	6	9	12	3	6	9	12	2	4	6	8	2	4	6	8
10	3	6	9	12	3	6	9	12	3	6	9	12	2	4	6	8
11	4	8	12	16	3	6	9	12	3	6	9	12	2	4	6	8
12	4	8	12	16	4	8	12	16	3	6	9	12	3	6	9	12
13	4	8	12	16	4	8	12	16	3	6	9	12	3	6	9	12
14	5	10	15	20	4	8	12	16	4	8	12	16	3	6	9	12

I get what you’re aiming at here, and it does have its internal logic, but I don’t like the ever-increasing disparity between the different armor types. Also, there should come a time where experience is the added value no matter what armor-type you’re wearing.
Also, for the sake of gameflow practicality, I’d prefer not to add another table that requires consulting. Just the opposite – I’d rather eliminate tables wherever possible.

I have this image in my head from the movie “Troy” of Achilles reigning supreme in his leather armor – and I want leather to count for high level characters as well.
It also doesn’t add up for me that DR will have value jumps (e.g. like your table displays from AC 4 to AC 5 for the “Large Spread, round normal” column).

ATM it makes the most sense to me that:
1. The armors will fulfill their DR full potential at BAB +2 / +4 / +6 / +8. Instead of consulting the table (as suggested in the OP) I’ll set it at [base DR = AC/2; magical bonuses don’t count]
2. Starting at BAB +10 and every +2 increase thereafter, the DR increases by 1 for any armor you’re proficient with.
3. Armor-associated DR doesn't advance passed BAB +20.
4. Armor-associated DR is gained from experience only. It doesn’t apply to monster/racial HD. Only BAB gained by actual level progression counts.

This would make Leather armor end up with DR 7/― and Full Plate end up with DR 10/―.
Breastplate would grant a level 20 Barb a total DR 13/―.

The numbers seem to add up.
Also, the above proposal will have no impact on monster taken as is from the MM_X books.

[nonsi]

OK. Here's a thought. Don't worry about DR and AC stacking at all, or whether or not it's level dependent. Just keep it as part of the equipment. If you feel like it's too powerful, just make sure that DR from conventional armor can be overcome by one of the three basic weapon damage types, then go nuts. Chain shirt would still retain its AC bonus no matter what, but would be overcome by a piercing weapon. Plate would be vulnerable to Bludgeoning, Hide to Slashing (or whatever you ultimately decide, those are just arbitrary, off the cuff choices). Magic enhancement could change it to X/-, but I'm not sure exactly how I'd do that at the moment, it's easy for that to get too fiddly.

I see the common sense in this approach (though I think you got chain and plate reversed), but it seems to me that this will overshadow armor-DR being mostly associated with combat experience and usage technique. Plus, it’s another level of complication that’s gonna be there practically all the time.

[Erloas]

It's really only a table in so far as it helps visualize a simple formula.

As for the disparaties\jumps, it's going to happen with any changing system, I had tried to get it to mostly align with the light\medium\heavy progression, but even there they have overlaps. Of course there could just be 3 progressions, tied to each type, all light the same, all medium the same, all heavy the same.

Trying to keep plate and leather as viable options just ignores that they are designed for very different classes. Does it make sense that the rogue and fighter get the same protection out of very different types of armor? To me it seems like my progression would give the biggest benefit to those that specialize in heavier armor, which seems like the point.

As for tying the increase to BAB instead of level, that would be easy, just change level on the table to BAB and it's done, tweak as necessary.

An addative progression rather than multiplitive would keep things closer, but also tends to make them less important at higher levels. It also makes the formula\table more complicated and has to be checked and changed more often for the players.

If you want it really simple and not really tied to armor, just use BAB/2, maybe +1/2/3 for light/medium/heavy. That would leave a 20 fighter at DR 11 in light or DR 13 in heavy. Or a 20 rogue at DR 8.

[nonsi]

It's really only a table in so far as it helps visualize a simple formula.

Still, it's another table to deal with.

Of course there could just be 3 progressions, tied to each type, all light the same, all medium the same, all heavy the same.

With the right values, this could work.

Trying to keep plate and leather as viable options just ignores that they are designed for very different classes. Does it make sense that the rogue and fighter get the same protection out of very different types of armor? To me it seems like my progression would give the biggest benefit to those that specialize in heavier armor, which seems like the point.

A level 20 fighter will gain DR 10/― from his Full Plate.
A level 20 rogue will gain DR 4/― from his Leather armor.

The Fighter has more HP, better AC, better DR and a shield - and its WBL is typically more combat-stats-oriented. The Fighter is obviously superior in straight combat in every possible way.

An addative progression rather than multiplitive would keep things closer, but also tends to make them less important at higher levels.

That's inevitable when scaling values gradually over a finite space of 20 levels.

If you want it really simple and not really tied to armor, just use BAB/2, maybe +1/2/3 for light/medium/heavy. That would leave a 20 fighter at DR 11 in light or DR 13 in heavy. Or a 20 rogue at DR 8.

Sure, but I'd prefer a more substantial gap between different armor types. I just don't want that gap to constantly increase (only to a point: BAB +8 in this particular case).
Also, I really don't want low levels to benefit from significant DR - where it's clearly not required.

[Erloas]

The Fighter has more HP, better AC, better DR and a shield - and its WBL is typically more combat-stats-oriented. The Fighter is obviously superior in straight combat in every possible way.

The thing is nothing you do in the armor system is going to change that. If your goal is to make a rogue more suvivable there are better ways to do that.

The main issue I would see is what would any system do to classes that are already good and can wear armor, like the divine classes? But in the end, anything you do with the armor system will affect everyone that uses armor. If you want to be much more selective on who gets the bonus and when, that is more of a feat or class ability sort of area.

If you think armor should provide more benefits than it currently does, then change armor to a system that makes sense and works for you. Adjust and balance the classes as needed, but don't make a base system like armor not have consistency because some classes use that system than others do.

If you don't want it to start working until level 5 or 10 or 8 or 12, then start the progression there, but that again starts to look a lot more like class abilities than a mundane property of gear.

[nonsi]

The thing is nothing you do in the armor system is going to change that. If your goal is to make a rogue more suvivable there are better ways to do that.

The main issue I would see is what would any system do to classes that are already good and can wear armor, like the divine classes? But in the end, anything you do with the armor system will affect everyone that uses armor. If you want to be much more selective on who gets the bonus and when, that is more of a feat or class ability sort of area.

If you think armor should provide more benefits than it currently does, then change armor to a system that makes sense and works for you. Adjust and balance the classes as needed, but don't make a base system like armor not have consistency because some classes use that system than others do.

If you don't want it to start working until level 5 or 10 or 8 or 12, then start the progression there, but that again starts to look a lot more like class abilities than a mundane property of gear.

My goal here is not to provide a class-driven solution, but to make armor better horizontally.

The thought here is that there’s only so much that low level characters can make out of their armor on one hand, but that there’s more to make out of armors that inherently provide better protection on the other... and still it takes time and experience to make the most out of them.
Beyond 6th level (real-world heroes about whom stories linger for centuries and even millennia), when characters start to deal with mythical creatures, they all learn to slowly maximize their armor protection to absorb and divert more of the damage – a slow process that the more melee-inclined characters are better at.

And… it’s a simple-to-implement solution that comes for free w/o requiring more feats or any other character resources. And it’s not meaningless on one hand and not broken on the other.
And given that Full Plate grants more than double the DR that the Barb gets at every level, and given that the Barb also benefits from it, and given that this solution is equally valid for core 3.5e and my overhaul project, I’m happy with the result

[Knaight]

Beyond 6th level (real-world heroes about whom stories linger for centuries and even millennia), when characters start to deal with mythical creatures, they all learn to slowly maximize their armor protection to absorb and divert more of the damage – a slow process that the more melee-inclined characters are better at.

You could tie it to BAB - every new attack is also an armor DR multiplier. This also makes it more useful for dedicated combat classes, and while this does help the rogue less that's not necessarily an issue considering just how good their main stat is (by physical stat standards).

[nonsi]

You could tie it to BAB - every new attack is also an armor DR multiplier. This also makes it more useful for dedicated combat classes, and while this does help the rogue less that's not necessarily an issue considering just how good their main stat is (by physical stat standards).

1. I would assume that heavy armor should grant higher DR than light armor, given all other parameters are equal. How do you model that with the above proposal?
2. Others hear have claimed that DR 4 is not enough to be meaningful at level 20. Not for heavy armor at least.

[Knaight]

1. I would assume that heavy armor should grant higher DR than light armor, given all other parameters are equal. How do you model that with the above proposal?
2. Others hear have claimed that DR 4 is not enough to be meaningful at level 20. Not for heavy armor at least.

1. Base DR = AC/2
2. Armor DR = Base DR*Number of attacks from BAB.

[nonsi]

1. Base DR = AC/2
2. Armor DR = Base DR*Number of attacks from BAB.

That will put Rogue 20 vs. Fighter 20 at DR 3 vs DR 16.
That kind of disparity will make the Unfettered Warrior character concept an obviously inferior choice and shift the meaningful difference from the character to his/her gear - the exact opposite of what I'm aiming for.

[Edit:]

Also, your formula makes Full Plate grant DR 4/― at 1st level.
I believe that this is too much.

[Nifft]

That will put Rogue 20 vs. Fighter 20 at DR 3 vs DR 16.
That kind of disparity will make the Unfettered Warrior character concept an obviously inferior choice and shift the meaningful difference from the character to his/her gear - the exact opposite of what I'm aiming for.

Make armor penalize AC and give significant DR. Now instead of wearing heavy armor and getting both, you need to decide which one you want more.

Then give a nod to the acrobats wearing full-plate and remove all Dexterity caps -- you can have both, but you pay more for having both, and your AC won't be as high as someone who only focused on dodging.

[nonsi]

Make armor penalize AC and give significant DR. Now instead of wearing heavy armor and getting both, you need to decide which one you want more.

Then give a nod to the acrobats wearing full-plate and remove all Dexterity caps -- you can have both, but you pay more for having both, and your AC won't be as high as someone who only focused on dodging.

I’m trying to maintain a delicate equilibrium here.
I want heavy armor to be obviously superior to light armor, just not to a point where the tin-can character (as a package) is obviously better than the unfettered warrior acrobat.
I don’t want light/medium/heavy armors to all be equally worthwhile, because that would automatically tilt the choice to the lighter armor.
Light armor has lower encumbrance, doesn’t limit (or hardly limits) your Dex and doesn’t restrict your movement or tumbling (and would probably take a smaller bite into your character’s cashflow). There are ways to narrow that gap back in favor of heavy armor, but that’ll come with a heavy toll in character resources (plural).

I’m not gonna alleviate armor restrictions based on BAB alone, because that’ll tilt things in favor of the heavier armors. There are feats for that.

I want to come as close as possible to a point where player-choices are based on the character they envision and as little as possible on char-op strategies.