Brainstorming a new damage system

[Teridax]

This idea is based on this thread on precision damage immunity, as well as this ongoing discussion regarding instances of damage and how ill-defined those are in 2e, along with prior discussions regarding the same topic. To summarize, here are some of my criticisms with damage as it is currently implemented in 2e:

Criticism of damage:

* Damage being split up into separate types means damage can often double- or even triple-dip into resistances and weaknesses: on one end, hitting multiple resistances at the same time can mean some mixed damage gets negated entirely, and on the other, hitting multiple weaknesses can make certain bits of damage hit disproportionately above their weight, making certain effects deceptively swingy.

* Resistances and weaknesses being a flat amount I think runs into problems where certain attacks can all too easily get negated by resistance, which I've seen happen with Starfinder's guns and their low damage. In other cases, it means even tiny amounts of damage become disproportionately stronger if they hit one or more weaknesses, adding to the swinginess of damage.

* Immunities, when not used sparingly enough, can easily shut down certain characters and make them feel like they have no options in certain encounters. This can range from magic-immune creatures such as golems and will-o'-wisps, to oozes with immunities to precision and mental effects, plus certain damage types, that can hard-counter classes like the Swashbuckler.

* Because damage can easily be split up, it's difficult to define what an instance of damage is, and that can have a real impact when determining the riders that occur when dealing damage, such as adding damage of a certain type via one ability to a thing that deals damage of that type. Additionally, split damage can make damage rolls more time-consuming than they need to be when not relying on automation and having to tally reduction from resistances.

* In addition to the above, I feel classes that are expected to trigger weaknesses more easily, like the Alchemist, are often given weaker damage as a result, as the expectation is that they'll be dealing a ton of damage by triggering weaknesses from mixed and/or persistent damage. When a monster doesn't have those weaknesses, however, those classes can easily feel deficient.

* On a more minor note, I feel damage types, rather than traits, are legacy design, as resistances, weaknesses, and immunities already factor in traits and damage types tend to be redundant when there's already a trait for it.

TL;DR: Damage as defined right now I think is often more complicated and swingy than it needs to be, suffers from a degree of legacy design, and is loosely-defined in ways that can give both the GM and player a headache.

IMO these issues are largely baked into 2e's fundamental design and are thus unlikely to ever change, nor would it be easy to overhaul this system. However, I still think it's worth considering a model that tries to avoid these same pitfalls. Here is my take on a model that could help streamline damage and make it smoother to run overall:

The changes:

1. Remove damage types. Damage instead has traits, such as bludgeoning, fire, or magical, and this damage is generally listed in the same way: damage with the fire trait, for instance, could just be listed as fire damage. Damage can have more than one trait, and so a Wizard dealing asteroid damage with falling stars to an enemy in the center of its burst would be dealing arcane bludgeoning fire damage.

2. All current instances of mixed damage are combined into a single instance of damage, which has all of the traits corresponding to the mixed damage's types. Any rider that adds damage on top, such as from a spellshape, blood magic effect, or other mechanic, adds damage to that same instance of damage. When you would combine damage for the purposes of resistances, weaknesses, bonuses, penalties, or the like, that damage is one single instance of damage. This could in fact all be defined under a trait, e.g. "salvo," that simply combines all different sources of damage into one instance.

3. Resistances, weaknesses, and immunities are no longer flat amounts, but instead status bonuses or penalties to defenses against the listed traits, ranging from +1 for minimal resistance to +4 for maximal resistance and immunity (and -1 to -4 status penalties for weaknesses). As normal with bonuses and penalties, you apply the largest applicable bonus and the largest applicable penalty each time when multiple traits apply.

4. In the case of immunities designed to block certain mechanical effects beyond damage and spell types, such as immunity to critical hits or death, define those immunities as monster abilities instead. For instances, oozes could have an amorphous monster ability that has them reduce critical hits to regular hits, and the undead trait could include rules to state that they're not slain instantly by death effects unless the effect also brings them to 0 HP.

5. Adjust monsters and class abilities accordingly: for instance, Champion reactions that grant resistances could instead grant a retroactive +4 bonus to the target's defenses, potentially changing the damaging effect's degree of success to something less severe.

TL;DR: Condense mixed and composite damage into a single instance that inherits traits corresponding to its components, change resistances, weaknesses, and immunities to status bonuses and penalties to defenses against listed traits, and adjust monsters and abilities accordingly.

There's more to be built upon this, like condensing the damage component of damage property runes into additional fundamental runes and having the property runes simply add a particular trait with an additional effect, but the core idea behind the above is to condense damage into just one instance each time and simplify rolling damage greatly, with resistances, weaknesses, and immunities adjusting attack rolls and saves rather than damage rolls. This should ideally streamline dealing damage, but should also soften certain counters, such that a caster going up against an enemy with a +1 status bonus against all magic doesn't have to also get their mixed damage reduced to 0 by high resistances, or a ranged martial doesn't get their single damage die reduced to 0 by an enemy with even a moderate resistance at low level.

This is of course a fairly drastic change from what we currently have, and I'm keen to know more about outliers and effects that would need special attention: what would need to be done to prevent the above from breaking certain things? Are there unintended consequences to the above you can think of? Would there be ambiguity that would need clarification or further rules?

[Loreguard]

First impression, didn't like it, but in retrospect I think it was more of an over-reaction.

By turning it into an affinity bonus/penalty it impacts damage in a less direct way, but meaningful way, and allows you to potentially have both weakness and resistance be able to trigger in meaningful way at the same time. I'll also confess it would make it feel like there was more ways to impact the rolls you get.

What I'm not certain about would be if I like the fact that, for instance if you had a minor ability that would have normally added a +1 fire damage to an attack. If that was used against something that had fire immunity, that it might for instance get a -4 affinity penalty because the sword was wreathed in flames, while the same sword, not wreathed in flames doesn't get the penalty. Is that worse than the complexity that you are trying to get rid of... maybe not, but it does feel problematic.

Maybe it provides additional complexity you don't want, but you might categorize effects that modify damage. Having minor (or some other term) effects, eliminate the bonus damage if the target has resistance to the type, rather than applying the effect to the whole damage. So in the above case, of +1 Fire(minor) damage would mean that rather than applying the additional damage and trait to the attack damage, it merely skips it if the opponent is resistant to fire.

I'd also suggest having immunity function similarly, stopping any damage and applied traits from effects with traits which they are immune to. Again if you make immunity rare enough, this should provide flavor and variations within battles, but ideally not create as much complexity as currently. There could continue to be variations with specific forms of immunity, (such as the immunity to critical hits) which can provide additional directions with how damage might be added to an instance, and its impact to the whole.

Another example of the use of proposed (minor) would be something like Infuse Vitality. Which currently adds vital damage. But I'd hate to see casting that spell giving a person a penalty for their normal attack and effectively do less damage in the end because of what was supposed to be a selective boost.

Anyway, that is a first thoughts, and mental review a bit later. So it is an interesting possibility.

[Teridax]

Thank you for the feedback; the idea of developing on different abilities that would counter specific bonuses is interesting as well, in my opinion. I do think though that if a monster has enough of a weakness to have a -4 status penalty to fire, then that +1 fire damage would be even more disproportionately powerful now, as it would turn into something like 23 damage against a level 20 enemy. This can make something like an otherwise weak consumable disproportionately effective, whereas now that consumable would have a higher chance to hit and crit, and therefore deal damage proportionate to its own.

I do agree with making immunity rare, though still present. My issue with it now I think is that immunity, on top of being overused, has some overlapping meanings at the moment: on one hand, it's used to represent a monster taking no damage of a certain type, e.g. fire immunity, but it's also used to state that a monster is unaffected by certain mechanics, e.g. immunity to death. I personally think immunity ought to be extremely rare, and when it does apply it's often better-served by a bespoke mechanic: this is already the case with undead and void damage, for instance, where the void healing ability of undead states they're unaffected by void damage, instead of providing generic void immunity. In many cases where immunity is currently applied, I do think strong resistance would be a better fit: for instance, elementals being immune to their own element to me makes about as much sense as a flesh-and-bone creature being immune to unarmed attacks from other flesh-and-bone creatures, so while resistance might be an intuitive thing to apply in my opinion, total immunity not so much.