As I understand from the podcasts and blogs and other posts here on the forums, Resonance is incredibly controversial. And I believe we almost universally agree that it doesn’t work in its present form. So I am going to put forth why I think it’s poorly designed and how I would go about fixing it.
Having played both D&D 4e and 5e, I see Resonance as taking the worst parts of 4e’s arbitrary “you can only use 3 daily use magic items a day” rule and 5e’s attunement system and combining them. Now I understand that the purpose of the resonance system is to curb spellcasters’ ability to use scrolls, wands, and staffs to break out of their limited daily spell preparation limit.
However, in attempting to accomplish this, I believe that it fails on several fronts. Firstly, it penalizes martial characters just as much if not more than it penalizes casters. For example, let’s look at a level 9 martial. Base you have 9 resonance points. It’s reasonable to assume you’ll have found some kind of magic weapon (1), maybe some armor (2), and you’ve got the most strength so you have the party’s bag of holding (3). After that one encounter with a bunch of annoying archers you found some bracers of missile deflection (4). You know you will be entering the Lava Cave of Certain Death, so you get your wizard to make you a lesser ring of fire resistance (5).
In the end you have spent 5 of your 9 resonance. So you have 4 resonance which seems kind of reasonable. But then you have to remember that to actually use your bracers or bag of holding it costs and additional resonance. Then if you get hurt and need a potion, that’s one more. Now you only have 1 resonance remaining. Granted you are allowed to “overspend” but critically failing an overspend means you can’t use magic items at all for the rest of the day.
Being a caster doesn’t really change much. You don’t need magical weapons or armor, but there are still plenty of permanent magic items that are useful regardless of being caster or martial. In my 9th level wizard for the playtest I have 10 resonance with 6 spent on permanent items. Still leaves me with 4 resonance to split between the staff, scrolls, and potions.
The second failing I feel is the added bookkeeping without benefit. Not only do you have to track uses per day of the individual items but you also have to track their resonance costs as well. How many items did you invest? How many uses of items do you have left? How many times did you overspend? How many charges are on your wand? Did you use that aeon stone ability already? You end up tracking a lot of this information twice and there doesn’t seem to be any benefit to doing so.
The third problem is the narrative and “magicalness” of magic items. Potions/oils are supposed to be self-contained spells that literally anyone can use just by drinking/applying them. No casting ability needed at all. But now it only works if the person has resonance remaining? And if you don’t have resonance and drink the potion, it’s still gone. You can’t undrink a potion.
So here is my suggestion for fixing Resonance. Chop off the Charisma modifier and just make it flat level. Any items that require charges/uses per day instead pull from this resonance pool. Permanent magic items and consumables no longer use the resonance system at all. To counter-balance this, we can slightly increase the cost of these items to make them less accessible. If we include wands in this, that might make them too powerful (basically a staff with more charges and only 1 spell), so maybe let them keep their own pool of charges. So only activated abilities of permanent items and staffs use resonance, with consumables and wands keeping their typical usage requirements.
So if we go back to the above 9th level characters, the martial character has not spent any of his Resonance up front and now only has to worry about spending his Resonance on his bracers which will likely mean that he rarely if ever runs out of resonance. Maybe he can even invest in some trinkets now. The wizard that I made however, similarly does not spend any Resonance up front, but now those 10 Resonance Points are going to be divined amongst a Spell Duelist’s Wand, an Aeon Stone, a Wayfinder containing said Aeon stone, a Phylactery of the Occult, and a Lesser Staff of Divination. Which means that I will generally get 2 uses out of each of those each day. Which is still significantly less than in 1e.
Your whole example falls apart when the fighter doesn't have the bag of holding. It makes no sense to have it on him in the first place. It's good on characters with low strength.
The bookkeeping is not more of a problem than it is to keep track of your prepared spells. So that's not really an argument against it.
Your third argument is just an argument from fluff and has no weight. The magic in the world of pathfinder doesn't follow any logical rules. If Paizo says that this is how they want it to be then that's how it works.
Your whole example falls apart when the fighter doesn't have the bag of holding. It makes no sense to have it on him in the first place. It's good on characters with low strength.
Falls apart is a little strong. Replace the bag of holding with any trinket, boots of bounding, or even a ranged weapon that the fighter falls back on. Any character can easily burn through resonance with permanent magic items, leaving little left over for potions.
The bookkeeping is not more of a problem than it is to keep track of your prepared spells. So that's not really an argument against it.
While I personally don't mind the bookkeeping, I'm playing an Occultist in 1e right now. I know quite a few people that don't play casters specifically because it requires too much bookkeeping. So adding additional bookkeeping to the game is a legitimate concern.
Your third argument is just an argument from fluff and has no weight. The magic in the world of pathfinder doesn't follow any logical rules. If Paizo says that this is how they want it to be then that's how it works.
This is a role-playing game so "fluff" and "feel" are certainly concerns that carry weight. People want to come and play a mighty champion of arms that cleaves through swaths of enemies. A rogue who can move quietly as a whisper, valuables simply vanishing into thin air right in front of their owner's eyes. A wizard who calls upon the powers barely within his control to shape the world around him. Even if something is mechanically sound, if people don't feel their characters isn't that something to worry about?
As to magic in the world of pathfinder not following any logical rules, I couldn't disagree more. Vancian Casting is incredibly logical and systematic. Spells do one thing, they fit into specific slots, and you get so many slots per day. You have specific requirements for preparing them and casting them. Jack Vance's The Dying Earth was published way back in 1950. D&D and Pathfinder have been using this system since the 1970's. So I'm not sure what you mean at all.
To your final point, if you find problem with arguments from fluff, then I'm not sure how "because Paizo says so" is a more sound argument. In fact, Paizo has already said on a number of occasions that Resonance is one of the more experimental systems to be included in the playtest and is most likely not going to survive the playtest in this exact implementation.
If you are concerned about fluff... Creatures can hold magical essence up to a point where their bodies can't take anymore. You are welcome.
By excluding consumables from using resonance, you undermine the key purpose of resonance. As a means of creating an economy which reduces the number of non-class significant spell-like abilities that can be triggered in a day.
If you leave wands with charges and resonance cost, it just means people will stock up on large quantity of scrolls.
While the right starting quantity of resonance is certainly a hard question. It think the biggest concern I have seen was people concerned about the risk of running out of resonance, and being stuck in a situation where they need to drink a healing potion and having already used their resonance for the day, and not wanting to risk the flat roll on getting the effects of the potion.
Here is a potential rule that might help those worried about potions, borrowing a bit of an idea from the buccaneer archetype. Have potions use resonance, unless the person is out of resonance. Before resorting to the Flat Check, they use a pool of potion-reserve which equals the character's CON modifier. (or potentially Con modifier + some constant number) If the last point of this reserve gets used, the character gets the sick condition for an hour, but the potion also takes effect. Subsequent potions require a flat check and resonance use. Failure of the check might make the drinker sick again, and wastes the potion. The sickness would be referred to as Resonance Toxicity. Potions taking an actual physical toll on the body as it triggers the built up magic.
Oh... the above would apply for potions and elixirs. But alchemists would of course still not have to pay resonance for their infused elixirs since they are already tied to them.
Actually, animals and other non-sentient creatures might use this CON based form of pseudo-resonance, if they are fed a potion.
By excluding consumables from using resonance, you undermine the key purpose of resonance. As a means of creating an economy which reduces the number of non-class significant spell-like abilities that can be triggered in a day.
And I get that, don't get me wrong. My complaint is mostly in how it seems to be applied to a degree that you often have to spend 2 or more Resonance to get any effect at all, even ones that aren't game-breakingly powerful high-level spells.
Like the bracers of missile deflection in my first example. Just to block one arrow, it takes 2 Resonance. 1 to invest, 1 to activate. A lesser staff has 2 charges. So to cast one spell, you need 1 Resonance to activate, 1 charge from the staff, and 1 Resonance to activate. I mean the staff itself has 1/5 the charges a 1e staff has. Isn't that a significant limitation in and of itself?
And we could probably speak volumes over how the system screws over the Alchemist class. It would be like a wizard or cleric giving up spell slots to wear a hat of disguise.
If you leave wands with charges and resonance cost, it just means people will stock up on large quantity of scrolls.
Now I'm just going to speak from experience, so maybe what happens at your table is very different. But in playing wizards for like 10 years, I have never run out of spell slots. And that honestly is not from stock-piling scrolls, staffs, and wands.
Consumable items are expensive (in 1e at least) and should be expensive. Seriously, a fully charged 4th level Wizard spell wand is 21,000 gold (in 1e). I never buy wands outright because of the expense. They are free spells which I'm more than willing to admit are very powerful.
Spells overall have been nerfed. Cleric/Druid/Sorcerer/Wizard all get fewer daily spell slots. Staffs and Wands have significantly fewer charges than their 1e counterparts. I don't really see why resonance is needed on 1-shot consumable items. If you really want to dissuade people from stockpiling, just make them more expensive.
Here is a potential rule that might help those worried about potions, borrowing a bit of an idea from the buccaneer archetype...
I can appreciate the suggestion, but it's making a system that I already think is over-complicated and unnecessarily more so.
The Paizo developers created a loophole for resonance that favors martial characters. Magic items cost resonance when worn or activated. A sword is not worn, and most magic swords are not activated. Thus, they don't cost resonance. Likewise, carrying a bag of holding does not cost resonance, but opening one does.
In contrast, a magic staff has to be invested to be used, despite being held rather than worn. "Investing a new staff takes 1 hour, but you can invest a staff as part of your daily preparation without adding any additional time to the preparations. (page 379)"
The fluff of resonance bothered me, so I created a thread about it during the playtest previews: Interpreting Resonance. I added three more interpretations after the original six based on other people's ideas. The previews had given us enough information about resonance that the thread was still valid after the rulebook was released.
The main problem with resonance is that it is complicated with extra bookkeeping. A lot of magic items, such as weapons and staves, have their own twists to the general resonance rules. Alchemists, a class that uses resonance regularly, had to rewrite several aspects of resonance, too. I had hoped that Pathfinder 2nd Edition's magic items would be simpler.
Like the bracers of missile deflection in my first example. Just to block one arrow, it takes 2 Resonance. 1 to invest, 1 to activate. A lesser staff has 2 charges. So to cast one spell, you need 1 Resonance to activate, 1 charge from the staff, and 1 Resonance to activate. I mean the staff itself has 1/5 the charges a 1e staff has. Isn't that a significant limitation in and of itself?
The Bracers of Missile Deflection take one resonance when put on and then one resonance for each reaction that deflects a missile. If the wearer deflects 3 missiles during the day, that is only 4 resonance rather than 6. However, due to the 10 minute cooldown between deflections, using the bracers 3 times would require 3 separate encounters with enemy archers. Why does it have a cooldown? Isn't costing resonance and giving only a +2 bonus to AC enough of a limit?
As for staves, a Pathfinder 1st Edition staff requires sacrificing a high-level spell in the morning to recharge it by one charge. The PF2 staff recharges a couple of charges when invested in the morning, which costs only one resonance. Thus, PF1 staves are best recharged during downtime, but PF2 staves recharge on a multi-day dungeon delve.
Likewise, carrying a bag of holding does not cost resonance, but opening one does.
They changed that in errata 1.2.