I am looking at the encounter building rules and they are based on Party Level. If I want to create a more open world, sandbox style situation, what is the best method?
The thing that seems easiest is to assume any given encounter is rated as"Standard" for it's level. So, an encounter of 4 4th level monsters is a Level 6 encounter if I am reading the math right. If the party is 5th level when they engage the encounter, it is considered Sever for them, but if they are 8th level is is considered Trivial. Actual XP awards for the encounter would be based on their level when they engage it.
If I were creating an open world, sandbox style situation, first I wouldn't worry about how badly your players hammer everything since they are likely to fight everything with full resources every day. I still remember my PF1 players going through Kingmaker and my 5E players doing Out of the Abyss, they hammered every sandbox style of encounter they faced because they had no need to preserve resources.
Now that being out of the way, a single equal level challenge or two with some lower level minions is generally a pretty good encounter for a standard 4 or 5 person party in a day. They won't have a tremendously difficult time beating them unless the monster has some kind mobility that allows them to protect themselves from direct attack given the short range of most attack capabilities in PF2.
A single monster of +2 to +4 would be a very tough challenge for most parties.
Yes, a group of monsters 4 levels lower would be pretty trival for a party unless they had some kind of special attack that was difficult to counter like all being to fly and launch breath weapons against a party with minimal ranged ability. You should think about that as well. If you had a group of flying gargoyles with bows that were 4 levels lower against a party of melees with casters using 30 foot range cantrips, then obviously the challenge is going to be much harder than it appears on paper.
If you want to create attrition in PF2, all you have to do is not give them hours of downtime. In 10 minutes they cannot get back that many hit points. They literally need hours as you stated to get back hit points from a low number, especially if they level.
Well, I will simply assume you really don't believe that's an answer good enough. (Hint: if "all you have to do is not give them hours of downtime" that means "the whole adventure will be over, the sandbox emptied, in hours instead of weeks") Obviously you realize the value of a D&D-ish game to offer support for what you called the AD&D gaming style where you simply must rely on nightly rests - not in the short term (that's why we have Clerics) of course, but in the long term.
All I'm doing here is pointing out that far from offering advice on how to achieve this in their latest game, Paizo doesn't even seem to remember that the playing style exists.
I am looking at the encounter building rules and they are based on Party Level. If I want to create a more open world, sandbox style situation, what is the best method?
The thing that seems easiest is to assume any given encounter is rated as "Standard" for it's level. So, an encounter of 4 4th level monsters is a Level 6 encounter if I am reading the math right. If the party is 5th level when they engage the encounter, it is considered Sever for them, but if they are 8th level is is considered Trivial. Actual XP awards for the encounter would be based on their level when they engage it.
I think so. You use the same numbers both to calculate the difficulty of the encounter and the xp awards. (The exception is when you have more or less heroes in your party than the default 4).
The xp amount/award of a monster is relative, not absolute. Everything starts with the party's level (and the game pretty much recommends every hero to be that same level).
So a level 4 monster is worth 60 XP to a level 3 party, 30 XP to a level 5 party and 15 XP to a level 7 party. The exact same monster in all three examples. See page 489 of the rulebook.
You would use this number (say "30 XP") both to sum up the encounter's worth of xp, and as an individual xp reward (to each of the four PCs)
Now, an encounter where all the monsters total 80 XP is "moderate". If the total is 60 XP it's "low" and if 120 XP it's "severe". Don't mistake these epithets for 5th Edition lingo - any encounter worth more than 60 XP or so would definitely qualify for "deadly" in 5th Edition. What Pathfinder calls "severe" would require an entirely new "insane" category in 5th Edition, and "extreme" would be "off the scale" Everything is much more dangerous here!
Anyway, if our level 5 party meets three of these level 4 critters, that's a 30+30+30=90 XP encounter. Assuming they win, each of the four heroes get 90 XP for their trouble, and you always need 1000 XP to reach the next level.
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Now then, to your sandbox: "what is the best method?"
I don't understand your reasoning with your "Standard" rating, so I'll simply explain from my own starting point:
As you will realize from the above, PF2 concerns itself with a fairly narrow level range of monsters. That is, it doesn't do "bounded accuracy". You can't just plop down a level 10 monster in your sandbox and expect the fledgling heroes to survive long enough to run away until they're maybe fifth level.
So if you run PF2 on default settings I would definitely recommend you create the illusion of a sandbox, instead of a true "old school" sandbox. That is, the game is intended for challenging fights where every monster is just about your own level. Adventure Paths are certainly constructed this way. At level 4, they just happen to mostly encounter level 2-6 forest monsters. At level 8, they mostly encounter level 6-10 forest monsters. With experience a GM can even level up or down monsters on the fly.
If you want the real deal, you might want to run the "proficiency without level" variant. It's detailed in the GMG but it essentially boils down to simply "subtract level from every roll or DC". The reason is that this transforms the game to be much more like 5E's bounded accuracy; heroes can now face monsters 8 levels above them and maybe not die, just like they could face monsters 4 levels above them in the default game.
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The other question revolves around attrition. PF2 is built around the assumption heroes are fully healed at the start of every encounter.
As you probably realize, this means that low-difficulty encounters lose pretty much their reason to exist (except for the occasional story reason, and when you want the players to feel suitably awesome), that is, they don't have the power to slow down the heroes. (The party simply relies on their martials, with casters "running on idle" i.e. using cantrips and focus spells only - this way the party can take on almost an unlimited number of "low" encounters, one at a time for hours and hours on end if only spaced out sufficiently. And since we're talking sandbox play, the heroes can nearly always stop marching forward to get the downtime they need)
It also skews the balance between martials and casters. If the only resource a martial cares about is easily replenished, that favors them. And casters are not powerhouses in PF2. Anything that slows down martials is probably a good thing. (At least for a classic sandbox that takes place during levels 1-10 the power move would probably be to ONLY play martials with a sole combat medic, and skip wizards etc entirely. This lets you mow through the sandbox at record speed, unimpeded by the need for casters to regain spell slots. Just restrict the Cleric to cantrips and reserve her spell slots for emergencies, and you're all set to be the Energizer Bunny of parties!)
I suspect that even if martials too need to rest for the night for their resources (=hp), that will still not make casters overpowered. In my experience, the average Fireball is only slightly better than a martial having a good round, so playing in a campaign style that is generous with spell slots (relative to hit points) is probably very workable.
If you want PCs to rely on and conserve their hit point totals you need to tweak the game in various ways:
you obviously need to restrict Medicine and its assorted feats, as well as certain features of any class you think the players will select. Case in point: the focus point based healing of Champions. Paizo will be of zero help here, and I haven't seen a comprehensive list of sources of "free healing".
unless you want one character played in the combat healing mode (a Cleric, for instance) to be near-obligatory you will probably want to introduce other complementary healing. That is, while you will want to remove Medicine's ability to heal you every 10 minutes all day long, you might not want to remove it completely. In plain terms: you might want something like charges, that provides a certain number of healing doses a day. Not zero doses, but not unlimited doses either.
any chain of encounters where the first encounters are meant to attrit the heroes for the final fight likely needs to go easy on the characters, meaning that I would avoid monsters above the party level until you know how much punishment the party can take.
This is because PF2 is simply not designed for your character's maximum hit points to last all day. A Fighter with 100 hp is expected to potentially have to use all of those in a single encounter. (Not every encounter of course) All balance is squarely designed for the single encounter. This is why you need some sort of replenishment during the day - unless you're fine with the adventuring day to end after the first challenging fight each day.
Whether you do this by liberally sprinkling loot caches with healing potions or introduce some kind of "healing surges" or simply simplify Medicine to "a successful check restores all lost hit points, but the character is then immune for four hours" or whatever is up to you. Good luck!
Either that or you double the hp totals of every character (but not monster) so that heroes can be expected to keep trucking even after losing a sizeable chunk of their hp.
A character's hit points are renamed "Wounds". A character also gets a number of Vitality Points equal to his maximum Wound Point total.
Damage is taken from Vitality before Wounds. Healing is applied to Wounds before Vitality.
At zero Vitality you're Fatigued. (When you have 1 or more points of Vitality, you're no longer Fatigued unless some other source made you Fatigued. Then you still need to rest for a night).
You automatically regain all lost Vitality (but not Wounds) after a short rest (10 minutes or 1 hour, your choice).
You might consider some healing spells to heal Vitality before Wounds (or not Wounds at all). Here's a good example.
As you hopefully realize, this suggestion is meant as a half-way point between default PF2 and maximum-grimness AD&D. Attrition is focused on "can we defeat these monsters without going into the red - that is without anyone losing more than their maximum hit point total". If you do, all's well. If you don't, you will still have full Vitality for the next fight so no need to worry about its balance, but since you suffer "Wounds attrition" you will eventually be forced to either stop for the day or start using limited resources (spells, potions etc) that also will eventually force you to stop for the day.
I am looking at the encounter building rules and they are based on Party Level. If I want to create a more open world, sandbox style situation, what is the best method?
The thing that seems easiest is to assume any given encounter is rated as"Standard" for it's level. So, an encounter of 4 4th level monsters is a Level 6 encounter if I am reading the math right. If the party is 5th level when they engage the encounter, it is considered Sever for them, but if they are 8th level is is considered Trivial. Actual XP awards for the encounter would be based on their level when they engage it.
The way I do this in my sandbox game is to pick a tuning level for an area and build encounters around that. I tie mine to the dungeon level, but there’s no reason you have to do that. This lets me have a range of encounters, so everything feels a little more organic, but it also lets me lean on the tools the system provides (especially the Treasure by Encounter table in the GMG).
This is also why I like using Proficiency without Level. It gives me a much wider range over which I can build encounters, so things don’t become obsolete quite as fast, but I can also include higher level creatures without blowing things out past an extreme encounter.
Edit: Just read this page, and the attrition discussion is still going…. This style also works fine with attrition (in dungeons, since attrition has never worked very well in wilderness exploration) if you create time pressure by dynamically playing your dungeon. I say this from experience, running a game where PCs don’t go into every fight at max HP. I use adversary rosters and restocking to great effect to create the impression the dungeon isn’t safe, and that taking time out to rest has an opportunity cost.
You're really asking this? Paizo owns PF, not 5E. They responded to their PF base because that is their fan base and who they were listening to when designing PF2. Nearly everything I see in PF2 is criticisms levered at PF1.
1. PF1 isn't balanced at higher levels: Now it is balanced at higher levels unlike say 5E, which min-maxers can still very much build into a DM nightmare game. I don't care how many 5E people tell me that never happens to them or how they can DM against it, the fact is 5E still very much allows highly imbalanced characters that make life more difficult for the DM. I have not seen that in PF2 yet up to level 12. If this imbalance occurs at later levels, I will make sure to bring it up.
2. Martial Caster Balance: Martials and casters are very balanced against each other.
3. Why can't APs take us all to level 20? What's the point of these level 20 abilities if no one ever reaches level 20?: Now the APs run to level 20 and are balanced to level 20.
The design of PF2 was specifically made to fix metagame balance issues with PF1. Balance was the great problem of PF1. And I would say is even a problem in 5E if you use additional options like multiclassing, magic items, and feats. PF2 ensured balance with feats, multiclassing, and magic items.
I figured you understood PF2 was directly created to fix the problems in PF1 with a heavy focus on balance and was not interested in becoming a different version of 5E. Is it perfect? Nope. Did it accomplish what it set out to accomplish? I would say yes, very much so. It addressed every major issue I saw leveled at PF1 over its decade plus run.
Everything is much more dangerous here!
