Damage reduction as an alternative to "minor" or "major" resistance

[Greywander]

A while back I posted a thread (https://forums.giantitp.com/showthread.php?637633-Major-and-minor-vulnerability) about breaking resistance and vulnerability up into minor/moderate/major categories, so that there was some degree of gradation instead of a simple binary yes/no. Part of the idea was that minor resistance would be easier to implement into player options, since it would be less strong than normal resistance, while still giving you a bonus and fitting to a theme. But the general consensus of that thread was that this was probably more trouble than it was worth.

So I was thinking that perhaps an acceptable alternative would be to combine damage reduction with resistance to approximate "minor" and "major" variants of resistance. Damage reduction with no resistance would be the "minor" version, while using both together would get you the "major" version, and resistance by itself would continue to fill the "moderate" version. With this in mind, it makes sense to tweak the rules regarding damage reduction and resistance such that the damage reduction gets applied after resistance.

Then there's the question of how to implement the damage reduction itself. We could just give a flat number, potentially giving more or less to certain creatures, races, or classes, but it might make more sense in the context of 5e to stick with a binary yes/no implementation: you either have damage reduction, or you do not. With that in mind, damage reduction should probably scale as you level up, and using proficiency bonus seems like the simplest way of implementing that. Now, there is an issue with damage reduction, and that's that it can potentially reduce the damage to 0. That's why HAM is such a strong feat on a 1st level variant human; a lot of the monsters you face at 1st level can have their attacks mostly or completely nullified by HAM. So instead of using flat proficiency bonus, it might make more sense to use proficiency dice, scaling from 1d4 at +2 up to 1d12 at +6 (not sure what to do for monsters with +7 to +9, though; maybe just 1d20 for +7 and up?). That way, you still have a chance of rolling low and taking damage, even from a weak attack.

So to summarize, if you had a trait that gave damage reduction against a specific damage type, that reduction would start at 1d4 at 1st level, and increase one die size every time your proficiency bonus increases, up to 1d12 at 17th level. If you also have resistance, then resistance applies first, then the remaining damage gets further reduced. This allows us to simulate differing levels of resistance. It might make sense to give this form of damage reduction its own special name, e.g. "fire protection", "cold protection", etc.

I was also thinking about how this might also be applied to vulnerability. We could apply the exact same logic, but in reverse: instead of reducing damage, the damage gets increased (if damage reduction is "protection", lets call this "weakness"). It also makes sense for this increase to happen before vulnerability is applied, so that if you're also vulnerable, then that damage increase gets compounded. One big problem, though, is the scaling. It doesn't make sense for a weakness to scale as you level up. However, it might make sense for it to scale as your opponent levels up. So the damage increase might relate to the attacker's proficiency bonus. The only problem with that is that it isn't clear how non-creature damage sources should be handled, e.g. traps or environmental hazards. So perhaps a better way to handle it might be to apply +1 damage per damage die (minimum of +1, e.g. for flat damage with no dice). This means a creature with fire weakness would be taking +8 extra damage from Fireball, for example, which would get doubled if the creature was also vulnerable.

Does this seem simpler and easier to use? Would you be interested in using these? Obviously this would pretty much only apply to homebrew, since official material isn't going to be using these, but you can make your own tweaks to existing monsters or races as you see fit.

[Kane0]

Seems fine (if you want these extra steps of granularity), except how do you handle when something has both resistance and weakness?

[Greywander]

Seems fine (if you want these extra steps of granularity), except how do you handle when something has both resistance and weakness?
If protection applies after resistance, then it makes sense that weakness would also apply after resistance. Likewise, protection would apply before vulnerability. This would allow you to temper a weakness/vulnerability by choosing a race/class combo that gets the corresponding protection/resistance. Vulnerability is harsh, but with protection it becomes a lot less harsh.

And actually, perhaps I was overcomplicating it. Protection could simply mirror weakness by reducing the damage by 1 per damage die (minimum of 1). This would make protection strictly weaker than resistance (and likewise weakness would be strictly less potent than vulnerability). This could then pave the way to implementing another aspect of this concept, which is how these would stack.

In the previous thread, one of the things I wanted to implement was that having three or more sources of minor resistance would "upgrade" into a source of moderate resistance (but would only ever count as a single source of moderate resistance, no matter how many sources of minor resistance you had), and likewise having three or more sources of moderate resistance would upgrade to major resistance. The problem with using proficiency dice for protection is that it isn't always strictly worse than resistance (which might be a good thing, since it adds variety), so this sort of stacking and upgrading wouldn't really work. But if protection is strictly worse than resistance, then we could just redefine protection as minor resistance. Instead of getting protection and resistance from two separate sources to make them stack, you'd need three sources of resistance to upgrade to "major resistance", which would be resistance + protection.

But maybe that's also more trouble than it's worth. Keeping them separate might be easier, even though it would also be easier to stack protection and resistance.

[quindraco]

You can certainly hand out damage reduction to players, but I don't see the point of using a die instead of a static amount (e.g. Heavy Armor Master already provides non-magical weapon B/S/P reduction, but the amount is 3, not 1d6). Resistance is a flat 50% - you don't roll to see how much you resist - so I don't see a compelling reason to roll how much you reduce, other than aping the reduction features on Monk and Goliaths that roll for the amount.

You could also hand out damage thresholds, by the way. That's like reduction but worse (Threshold X is strictly worse than Reduction X-1 for all X>=2). Supposing you're taking 1d12 damage per attack, the damage you take per attack is:


Normal: 6.5
Resistance: 3
Reduction 3: 3.5
Threshold 9: 3.5


The only problem with balancing Reduction and Threshold is that the CR guidelines don't care how many attacks a monster's DPR is broken up into, but Reduction and Threshold are both better when the same DPR is broken up into multiple attacks.

Anyway. Reduction and Threshold are both very easy, simple mechanics, and the former is already widely available, so you shouldn't have any difficulty persuading PCs to pick it up. Bear in mind that you need a lot of Reduction to even be worth noticing against low-volume high-damage attacks, while you need negligible Reduction to notice it against high-volume low-damage attacks.

Here's another list of taken damage values for a Tarrasque's bite (4d12+10), trying to set damage taken to three different tiers of resilience:


Normal: 36
Threshold 31: 30.13 + some loose change
Reduction 12: 24
Resistance: 17.75

[MoiMagnus]

The only problem with balancing Reduction and Threshold is that the CR guidelines don't care how many attacks a monster's DPR is broken up into, but Reduction and Threshold are both better when the same DPR is broken up into multiple attacks.

To be fair, there are already instances of this. Obviously, the "Heavy Armour Master" feat is one of the them, but something I dislike much more is the recent "Gift of the Chromatic Dragon" feat which gives resistance to one instance of damage (instead of resistance for one round), making it pretty bad against multi-attacks.

[Greywander]

You can certainly hand out damage reduction to players, but I don't see the point of using a die instead of a static amount (e.g. Heavy Armor Master already provides non-magical weapon B/S/P reduction, but the amount is 3, not 1d6). Resistance is a flat 50% - you don't roll to see how much you resist - so I don't see a compelling reason to roll how much you reduce, other than aping the reduction features on Monk and Goliaths that roll for the amount.
I suppose it was the competing desires of wanting to negate small amounts of damage entirely while also not wanting to negate small amounts of damage entirely. IIRC, goblins deal an average of 4 damage per hit. If the DM is just using average damage instead of rolling, then a damage reduction of 4 makes you completely immune to goblin attacks. The idea behind rolling the reduction is that you could still roll a low number and take a little damage, so over time you could still be worn down instead of being basically immortal.

In my second post, I reconsidered using the die for damage reduction. Instead, it might make more sense to make it mirror weakness, where the damage is reduced by the number of damage dice (minimum of 1). So if you have fire protection and you get hit with a Fireball, the damage gets reduced by 8. That's strictly worse than resistance (for damage > 1), scales naturally according to the damage dealt (rather, the number of damage dice rolled), and doesn't require any extraneous dice rolling.


The only problem with balancing Reduction and Threshold is that the CR guidelines don't care how many attacks a monster's DPR is broken up into, but Reduction and Threshold are both better when the same DPR is broken up into multiple attacks.
This is true, but I think this can actually be used to create interesting tactics. Right now, there isn't a significant difference between many weak attacks vs. one strong attack; the only thing that really matters is the total damage. Flat damage reduction, as with HAM, creates a distinction between these two, as now we're significantly more resilient against many weak attacks, but only marginally more resilient against one strong attack. You can also create a reverse situation with, say, something like Uncanny Dodge, where you can greatly reduce the damage of one strong attack, but can't keep dodging many weak attacks. Honestly, I'd kind of like to see this incorporated into the game, likely to create a rock-paper-scissors triangle between warriors, thief, and mages. But eh.

And anyway, as I said above, I've decided to change how protection works, so it's just a flat 1 damage reduction per damage die. Then it doesn't matter if it's one strong attack or many weak attacks.

[stoutstien]

You could also have damage reduction as resistance but cannot go below a number equal to the attacker's Prof bonus. So the goblin will always do at least 2 on a hit regardless.

[AdAstra]

I suppose it was the competing desires of wanting to negate small amounts of damage entirely while also not wanting to negate small amounts of damage entirely. IIRC, goblins deal an average of 4 damage per hit. If the DM is just using average damage instead of rolling, then a damage reduction of 4 makes you completely immune to goblin attacks. The idea behind rolling the reduction is that you could still roll a low number and take a little damage, so over time you could still be worn down instead of being basically immortal.

In my second post, I reconsidered using the die for damage reduction. Instead, it might make more sense to make it mirror weakness, where the damage is reduced by the number of damage dice (minimum of 1). So if you have fire protection and you get hit with a Fireball, the damage gets reduced by 8. That's strictly worse than resistance (for damage > 1), scales naturally according to the damage dealt (rather, the number of damage dice rolled), and doesn't require any extraneous dice rolling.

This is true, but I think this can actually be used to create interesting tactics. Right now, there isn't a significant difference between many weak attacks vs. one strong attack; the only thing that really matters is the total damage. Flat damage reduction, as with HAM, creates a distinction between these two, as now we're significantly more resilient against many weak attacks, but only marginally more resilient against one strong attack. You can also create a reverse situation with, say, something like Uncanny Dodge, where you can greatly reduce the damage of one strong attack, but can't keep dodging many weak attacks. Honestly, I'd kind of like to see this incorporated into the game, likely to create a rock-paper-scissors triangle between warriors, thief, and mages. But eh.

And anyway, as I said above, I've decided to change how protection works, so it's just a flat 1 damage reduction per damage die. Then it doesn't matter if it's one strong attack or many weak attacks.

It does sorta matter. In general big attacks will consist more of dice than numerical bonuses, while in weak attacks (or at least, attacks that come in twos and fours) those bonuses matter more. Spells especially do basically all their damage as dice, so they'll be affected most of all. Smaller dice will also be affected more than bigger dice, though that sorta thing tends not to be associated with the power of the attack quite as much, being more randomly distributed. Particularly on the player side, where wizards and rogues do almost all their damage as heaps of Sneak Attack and Fireball dice, whereas sword and board and Sharpshooter Fighters will be doing most of theirs through bonuses, you're going to see some differences. Vitriolic Sphere would get hammered by losing even one point per die, while a Great Weapon Master using a Greataxe basically wouldn't care.



I'm actually fine with that, to be clear. It's a pretty minor effect most of the time anyhow.